193 VOLUME 93 NUMBER 20 15 MAY 2012 News: U.S. Senate May Consider Law of the Sea Treaty Again, p. 194 News: Weather Extremes Could Affect Agriculture, p. 194 News: Report Says Earth Observing System Beginning a Rapid Decline, p. 195 Forum: Developing a National Stream Morphology Data Exchange, p. 195 Meeting: Understanding Planetary Caves, p. 196 About AGU: Newly Established AGU Awards and Lecture, p. 196 AGU Bookshelf: Navigating Graduate School and Beyond, p. 197 2012 AOGS–AGU (WPGM) Joint Assembly Early Bird Registration Deadline: 4 June Visit www.asiaoceania.org/aogs2012 to Register The explosive eruption of Alaska’s Mount Redoubt volcano in March and April 2009 provided a superb opportunity for studying volcanic lightning. The energetic explosions produced powerful volcanic lightning storms, the largest of which rivaled the intensity of the massive supercell thunderstorms that fre- quent the midwestern Great Plains. Although lightning often has been observed in the plumes of explosive volca- nic eruptions, only a handful of detailed studies have delved into the origins of vol- canic lightning. Active volcanoes tend to be situated in remote locations, where they are difficult to observe, and often have sudden, unpredicted eruptions. Even when the erup- tions are observed close at hand, the volca- nic clouds are intensely opaque, obscuring most of the lightning from view. Because of heightened seismicity 2 months in advance of the Mount Redoubt eruption, a group of researchers from New Mexico Institute of Mining and Technology and University of Alaska Fairbanks were able to install lightning mapping instru- mentation in time to observe the complete sequence of the volcanic lightning activity. Redoubt had already been heavily instru- mented by the Alaska Volcano Observatory, with instruments in place to measure seis- mic and acoustic activity. The study of volcanic lightning is important because it provides a means of remotely detect- ing or confirming eruptions that pose a threat to modern-day activities, such as global air traffic. Mount Redoubt is situated at the northeast- ern end of the Aleutian volcanic arc and is on one of the busiest cargo and passenger air- plane routes in the world. For example, dur- ing its 1989–1990 eruption a large commer- cial jetliner flew through an ash cloud from Redoubt, causing all four engines to tempo- rarily shut down and the plane to experience a precipitous drop in altitude [Brantley, 1990]. Fortunately, the crew members were able to restart the engines and land safely in nearby Anchorage, Alaska. Detection of volcanic lightning could confirm the presence of ash- rich clouds and help prevent future incidents. Imaging Volcanic Lightning Within days of learning about Mount Redoubt’s increasing precursory activity, four portable very high frequency (VHF) Lightning Mapping Array (LMA) stations were deployed along the west coast of the Kenai Peninsula, 80 kilometers east of Redoubt, and in clear line of sight of the 3.1- kilometer-high (10,200-foot) volcano (Fig- ure 1a). The mapping stations were set up outdoors in wintry conditions in late January and early February 2009. When a lightning discharge occurs, it pro- duces a succession of bursts of VHF radio emissions. The LMA remotely images light- ning by locating the sources of these VHF emissions. Water and ash clouds, while opaque in the visible spectrum, are fully transparent to radio signals, enabling one to effectively see inside the volcanic plume. Each LMA station accurately records the arrival times of the impulsive VHF sig- nals using GPS timing. The peak power of the incoming VHF radiation is recorded over successive 10-microsecond intervals, enabling tens to hundreds of impulsive events to be located per discharge [Thomas et al., 2004]. Mount Redoubt erupted explosively between 23 March and 4 April 2009, produc- ing more than 30 distinct explosive events of differing intensities and durations through- out the eruption (see http://lightning.nmt.edu/ redoubt). The largest explosions triggered intense lightning storms that lasted from 20 to 70 minutes and produced thousands of light- ning flashes. Smaller explosions produced fewer than 10 detected lightning discharges over spans of less than 10 minutes, and some produced no discernible lightning. All but two or three of the volcanic explosions were obscured from view by inclement weather, but all were readily detected at VHF. Clouds produced by the largest explosions reached altitudes of 10–19 kilometers, well into the stratosphere, and subsequently drifted down- wind, with lightning extending from 10 to 150 kilometers into the downwind plume. The explosively active period of the eruption cli- maxed on 4 April 2009 with the most power- ful event of the sequence. Following this, the eruption continued with the slow extrusion of a lava dome and no lightning. Comparison With Mount St. Augustine Eruption The electrical activity observed at Mount Redoubt was similar to that detected dur- ing the January 2006 eruption of Mount St. Augustine, which sits farther to the south in Cook Inlet. The Augustine observations, the first made using the VHF lightning map- ping approach, were obtained using two mapping stations that determined only the azimuthal direction to the lightning sources [Thomas et al., 2007]. That study identified two distinct phases in the lightning activ- ity: an explosive phase and a plume phase (Figure 1d), with the latter phase follow- ing the first after a slight delay. The same two phases are evident in the recent Mount Redoubt observations (Figure 1e), except that they tend to overlap in time [Behnke et al., 2012]. The overlap is likely due to the Redoubt explosions being both more ener- getic and of longer duration than those of Mount St. Augustine. The Mount Redoubt observations (Fig- ure 1e) showed that at the beginning of an explosive event the lightning radiation was very intense and essentially continuous, sim- ilar to the electrical activity identified as the explosive phase in the Mount St. Augustine observations. Seismic and acoustic mea- surements (Figures 1f and 1g) made within 12 kilometers of the vent confirmed that this initially intense lightning was associated with the individual volcanic explosions. Ani- mations of the located lightning data during the explosive event showed that the electri- cal activity initially consisted of innumerable small, randomly occurring discharges. Following this continuous period of lightning, the radiation in the plume phase became increasingly intermittent over time, similar to the Augustine observa- tions, with discrete discharges toward the end of the plume phase being separated by minutes of inactivity. The observa- tions showed discharges during the plume phase becoming larger in extent and dura- tion and occurring progressively down- wind of the volcano in the drifting plume. Flash rates during the explosive event pre- sented in Figure 1b ranged from 100 to 150 flashes per minute during the plume phase. In the largest explosions, such as those on 23 March and 4 April, flash rates are estimated to have been at least twice as high, comparable to observed lightning rates in supercell thunderstorms in the United States. Electrification Processes Of particular interest in volcanic light- ning studies is the question of how volcanic plumes become strongly electrified, includ- ing the roles of high temperatures, magma composition, ash, and gas content in this process. The Mount St. Augustine observa- tions indicated that there are separate elec- trification processes for the explosive and plume phases. During the explosive phase, nearly continuous electrical discharges were observed occurring close to the vent. Further, the onset of the lightning activity was concur- rent with the volcanic explosion, indicating that the ejecta were already highly electrified as they exited the vent. The combination of intense lightning at the vent of the volcano simultaneous with the onset of the eruption suggests that a silica- based charging process, in which ash is charged as magma fractures within the volcano, was acting during the explosive phase [James et al., 2008]. The continuation of large-scale lightning in the downwind plume suggests that the same gravitational sedimentation processes that electrify thunderstorms dominated during the plume phase. In this process, oppositely charged particles of different sizes become seg- regated because of their differing fall speeds. The size-segregated charging could have been a remnant of the explosive charging or of subse- quent in situ particle electrification processes, Spectacular Lightning Revealed in 2009 Mount Redoubt Eruption BY S. A. BEHNKE, R. J. THOMAS, P. R. KREHBIEL, AND S. R. MCNUTT Spectacular Lightning cont. on page 194 Fig. 1. (a) Locations of the Mount Redoubt and Mount St. Augustine volcanoes (triangles) and lightning mapping stations (squares) in Alaska. (b) Map view of very high frequency (VHF)– detected lightning activity during the explosive eruption at 23:29 UTC on 28 March 2009 (courte- sy of International Commission on Atmospheric Electricity).The uncertainties in the plan position of the lightning sources were approximately 200 meters or less.The lightning began over Mount Redoubt (marked with white crosshairs) and continued for 40 minutes as the plume drifted eastward toward Nikiski, Alaska (with increasing time coded by color).Twelve cloud-to-ground (CG) discharges (10 negative CGs (triangles) and 2 positive CGs (crosses)) were located by the Bureau of Land Management Lightning Detection System during the event. (c) Composite pho- tograph of in-cloud and CG lightning during the explosive eruption at 07:19 UTC on 28 March 2009, including an outline of Mount Redoubt (photographs taken from Seldovia, Alaska, 125 kilometers to the south-southeast, by Brentwood Higman; http://www.groundtruthtrekking.org/ blog/?p=849). (d and e) Electrical activity recorded during the explosive eruptions of Mount St. Augustine on 28 January 2006 and Mount Redoubt on 23 March 2009.The figures depict the peak power values recorded by a single station versus time, colored to indicate the number density of detected events (red is higher density; purple is lower density).The explosive phase is characterized by intense, nearly continuous VHF radiation.The plume phase is characterized by increasingly discrete individual discharges, corresponding to the vertical lines. (f and g) Acoustic and seismic recordings for the 23 March Mount Redoubt explosion.The onset of VHF radiation in the Mount Redoubt observations was delayed and less rapid relative to that of Mount St. Augus- tine and the acoustic Mount Redoubt recordings, likely due to the vent being on the far side of and 500 meters below the summit.
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volume 93 number 20 15 may 2012
news: u.S. Senate may Consider law of the Sea Treaty again, p. 194news: Weather extremes Could affect agriculture, p. 194news: report Says earth observing System beginning a rapid Decline, p. 195Forum: Developing a national Stream morphology Data exchange, p. 195meeting: understanding Planetary Caves, p. 196about aGu: newly established aGu awards and lecture, p. 196aGu bookshelf: navigating Graduate School and beyond, p. 197
2012 AOGS–AGU (WPGM) Joint Assembly Early Bird Registration Deadline: 4 June Visit www.asiaoceania.org/aogs2012 to Register
The explosive eruption of Alaska’s Mount Redoubt volcano in March and April 2009 provided a superb opportunity for studying volcanic lightning. The energetic explosions produced powerful volcanic lightning storms, the largest of which rivaled the intensity of the massive supercell thunderstorms that fre-quent the midwestern Great Plains.
Although lightning often has been observed in the plumes of explosive volca-nic eruptions, only a handful of detailed studies have delved into the origins of vol-canic lightning. Active volcanoes tend to be situated in remote locations, where they are difficult to observe, and often have sudden, unpredicted eruptions. Even when the erup-tions are observed close at hand, the volca-nic clouds are intensely opaque, obscuring most of the lightning from view.
Because of heightened seismicity 2 months in advance of the Mount Redoubt eruption, a group of researchers from New Mexico Institute of Mining and Technology and University of Alaska Fairbanks were able to install lightning mapping instru-mentation in time to observe the complete sequence of the volcanic lightning activity. Redoubt had already been heavily instru-mented by the Alaska Volcano Observatory, with instruments in place to measure seis-mic and acoustic activity.
The study of volcanic lightning is important because it provides a means of remotely detect-ing or confirming eruptions that pose a threat to modern- day activities, such as global air traffic.
Mount Redoubt is situated at the northeast-ern end of the Aleutian volcanic arc and is on one of the busiest cargo and passenger air-plane routes in the world. For example, dur-ing its 1989–1990 eruption a large commer-cial jetliner flew through an ash cloud from Redoubt, causing all four engines to tempo-rarily shut down and the plane to experience a precipitous drop in altitude [Brantley, 1990]. Fortunately, the crew members were able to restart the engines and land safely in nearby Anchorage, Alaska. Detection of volcanic lightning could confirm the presence of ash-rich clouds and help prevent future incidents.
Imaging Volcanic Lightning
Within days of learning about Mount Redoubt’s increasing precursory activity, four portable very high frequency (VHF) Lightning Mapping Array (LMA) stations were deployed along the west coast of the Kenai Peninsula, 80 kilometers east of Redoubt, and in clear line of sight of the 3.1- kilometer- high (10,200-foot) volcano (Fig-ure 1a). The mapping stations were set up outdoors in wintry conditions in late January and early February 2009.
When a lightning discharge occurs, it pro-duces a succession of bursts of VHF radio emissions. The LMA remotely images light-ning by locating the sources of these VHF emissions. Water and ash clouds, while opaque in the visible spectrum, are fully transparent to radio signals, enabling one to effectively see inside the volcanic plume. Each LMA station accurately records the arrival times of the impulsive VHF sig-nals using GPS timing. The peak power of the incoming VHF radiation is recorded over successive 10-microsecond intervals, enabling tens to hundreds of impulsive events to be located per discharge [Thomas et al., 2004].
Mount Redoubt erupted explosively between 23 March and 4 April 2009, produc-ing more than 30 distinct explosive events of differing intensities and durations through-out the eruption (see http:// lightning .nmt .edu/ redoubt). The largest explosions triggered intense lightning storms that lasted from 20 to 70 minutes and produced thousands of light-ning flashes. Smaller explosions produced fewer than 10 detected lightning discharges over spans of less than 10 minutes, and some produced no discernible lightning. All but two or three of the volcanic explosions were obscured from view by inclement weather, but all were readily detected at VHF. Clouds produced by the largest explosions reached altitudes of 10–19 kilometers, well into the stratosphere, and subsequently drifted down-wind, with lightning extending from 10 to 150 kilometers into the downwind plume. The explosively active period of the eruption cli-maxed on 4 April 2009 with the most power-ful event of the sequence. Following this, the eruption continued with the slow extrusion of a lava dome and no lightning.
Comparison With Mount St. Augustine Eruption
The electrical activity observed at Mount Redoubt was similar to that detected dur-ing the January 2006 eruption of Mount St. Augustine, which sits farther to the south in Cook Inlet. The Augustine observations, the first made using the VHF lightning map-ping approach, were obtained using two mapping stations that determined only the azimuthal direction to the lightning sources [Thomas et al., 2007]. That study identified two distinct phases in the lightning activ-ity: an explosive phase and a plume phase (Figure 1d), with the latter phase follow-ing the first after a slight delay. The same two phases are evident in the recent Mount Redoubt observations (Figure 1e), except that they tend to overlap in time [Behnke et al., 2012]. The overlap is likely due to the Redoubt explosions being both more ener-getic and of longer duration than those of Mount St. Augustine.
The Mount Redoubt observations (Fig-ure 1e) showed that at the beginning of an explosive event the lightning radiation was very intense and essentially continuous, sim-ilar to the electrical activity identified as the explosive phase in the Mount St. Augustine observations. Seismic and acoustic mea-surements (Figures 1f and 1g) made within 12 kilometers of the vent confirmed that this initially intense lightning was associated with the individual volcanic explosions. Ani-mations of the located lightning data during the explosive event showed that the electri-cal activity initially consisted of innumerable small, randomly occurring discharges.
Following this continuous period of lightning, the radiation in the plume phase became increasingly intermittent over time, similar to the Augustine observa-tions, with discrete discharges toward the end of the plume phase being separated by minutes of inactivity. The observa-tions showed discharges during the plume phase becoming larger in extent and dura-tion and occurring progressively down-wind of the volcano in the drifting plume. Flash rates during the explosive event pre-sented in Figure 1b ranged from 100 to 150 flashes per minute during the plume phase. In the largest explosions, such as those on 23 March and 4 April, flash rates are estimated to have been at least twice as high, comparable to observed lightning rates in supercell thunderstorms in the United States.
Electrification Processes
Of particular interest in volcanic light-ning studies is the question of how volcanic plumes become strongly electrified, includ-ing the roles of high temperatures, magma composition, ash, and gas content in this process. The Mount St. Augustine observa-tions indicated that there are separate elec-trification processes for the explosive and plume phases. During the explosive phase, nearly continuous electrical discharges were observed occurring close to the vent. Further, the onset of the lightning activity was concur-rent with the volcanic explosion, indicating that the ejecta were already highly electrified as they exited the vent. The combination of intense lightning at the vent of the volcano simultaneous with the onset of the eruption suggests that a silica- based charging process, in which ash is charged as magma fractures within the volcano, was acting during the explosive phase [James et al., 2008].
The continuation of large-scale lightning in the downwind plume suggests that the same gravitational sedimentation processes that electrify thunderstorms dominated during the plume phase. In this process, oppositely charged particles of different sizes become seg-regated because of their differing fall speeds. The size- segregated charging could have been a remnant of the explosive charging or of subse-quent in situ particle electrification processes,
Spectacular Lightning Revealed in 2009 Mount Redoubt Eruption
By S. A. Behnke, R. J. ThomAS, P. R. kRehBiel, And S. R. mcnuTT
Spectacular Lightning cont. on page 194
Fig. 1. (a) Locations of the Mount Redoubt and Mount St. Augustine volcanoes (triangles) and lightning mapping stations (squares) in Alaska. (b) Map view of very high frequency (VHF)– detected lightning activity during the explosive eruption at 23:29 UTC on 28 March 2009 (courte-sy of International Commission on Atmospheric Electricity). The uncertainties in the plan position of the lightning sources were approximately 200 meters or less. The lightning began over Mount Redoubt (marked with white crosshairs) and continued for 40 minutes as the plume drifted eastward toward Nikiski, Alaska (with increasing time coded by color). Twelve cloud-to-ground (CG) discharges (10 negative CGs (triangles) and 2 positive CGs (crosses)) were located by the Bureau of Land Management Lightning Detection System during the event. (c) Composite pho-tograph of in-cloud and CG lightning during the explosive eruption at 07:19 UTC on 28 March 2009, including an outline of Mount Redoubt (photographs taken from Seldovia, Alaska, 125 kilometers to the south- southeast, by Brentwood Higman; http:// www . groundtruthtrekking .org/ blog/ ?p =849). (d and e) Electrical activity recorded during the explosive eruptions of Mount St. Augustine on 28 January 2006 and Mount Redoubt on 23 March 2009. The figures depict the peak power values recorded by a single station versus time, colored to indicate the number density of detected events (red is higher density; purple is lower density). The explosive phase is characterized by intense, nearly continuous VHF radiation. The plume phase is characterized by increasingly discrete individual discharges, corresponding to the vertical lines. (f and g) Acoustic and seismic recordings for the 23 March Mount Redoubt explosion. The onset of VHF radiation in the Mount Redoubt observations was delayed and less rapid relative to that of Mount St. Augus-tine and the acoustic Mount Redoubt recordings, likely due to the vent being on the far side of and 500 meters below the summit.
As Earth’s climate warms, agricultural producers will need to adapt. Changes, especially increases in extreme events, are already having an impact on food produc-tion, according to speakers at a 1 May ses-sion on agriculture and food security at the AGU Science Policy Conference.
Christopher Field, director of the Depart-ment of Global Ecology at the Carnegie Institution for Science of Washington, D. C., pointed out the complex factors that come into play in understanding food security, including spatially varying controls and stresses, incomplete models, and the poten-tial for threshold responses. Factors that are likely to cause problems include increasing population; increasing preference for meat, which needs more land and energy inputs to produce; climate change; and increasing use of agricultural lands for biomass energy.
Extreme weather events, which are pre-dicted to occur more frequently in a warm-ing climate, are likely to affect crop yields, Field explained. The recent Intergovern-mental Panel on Climate Change special report on “Managing the risks of extreme events and disasters to advance climate change adaptation (SREX)” predicts a ten-fold increase in extreme heat this century under a moderate carbon dioxide emissions scenario. That would mean “the most severe heat wave in a decade is occurring every year,” he said.
Field added that agricultural yields have been increasing for all major crops over the last century, but in the past few years the rate of increase has slowed, possibly limited by warming. “For several major crops we’re
already seeing temperature sensitivity,” he said. He noted that investment in agricul-tural research has been decreasing in recent years, and many farmers have not been tak-ing steps to proactively adapt to projected climate changes. “We need to make food security a priority,” Field concluded.
Jerry Hatfield, laboratory director and supervisory plant physiologist at the U.S. Department of Agriculture’s Agricultural Research Service, also noted some changes that have been affecting agriculture. For instance, in Iowa, more of the annual precip-itation is occurring during early spring than has been observed previously. Increased precipitation in early spring has meant that farmers had 3 fewer days each year to work in their fields in the period 2000–2011 com-pared with 1970–2000. “In 2011 we planted 61% of the state of Iowa’s corn in 1 week,” he said. Farmers are also changing the types of crops they plant, increasing the amount of corn planted and decreasing other crops.
Hatfield also noted that continuing to increase yields will require the use of more and more water and could result in other negative consequences such as increased soil erosion.
Providing an example of how extremes are already affecting farmers, Jack Hedin,
a farmer and owner of Featherstone Farm, a Minnesota vegetable farm, said he had observed that the weather is less stable than it was just a decade ago. “My farm and liveli-hood have been greatly impacted,” he said.
“When we’re able to plant oats and peas in the middle of March, as we did this year, or harvest broccoli in the middle of Decem-ber, as we did last year,” Hedin said, farmers view these events with “ eye- popping disbe-lief.” However, “we’re seeing these types of outlying events more and more.”
Extreme events, such as prolonged heat or intense rains, severely affect day-to-day operations, Hedin said. He recently had to relocate some of his farming operations to drier ground after a severe flood. Although he is taking action to adapt his farm, reduce his farm’s fossil fuel use, follow good land use practices, and conserve soil and water, he noted that many farmers are not. “I have neighbors that are hostile to discussing the issue” of climate change, Hedin said.
Hatfield added that although farmers he works with often do not want to talk about global warming, focusing the discussion on how they can manage increased weather variability can help them plan for future change.
—eRnie BAlceRAk, Staff Writer
U.S. ambassador David Balton hopes that the third time will be the charm. The U.S. Senate’s Committee on Foreign Relations cur-rently is considering holding hearings for a third time regarding U.S. accession to the United Nations Convention on the Law of the Sea, a framework governing uses of the world’s oceans. The committee could hold hearings as early as this month, Balton, dep-uty assistant secretary for oceans and fisher-ies at the U.S. Department of State, said at the AGU Science Policy Conference on 2 May.
The Senate committee voted for the con-vention in 2004 and 2007, though a vote by the full Senate was blocked both times by some senators who are concerned about U.S. access to the seabed, potential loss of U.S. sovereignty, and other reasons.
However, Balton said there is broad bipar-tisan support for U.S. accession to the con-vention, which was adopted in 1982 by par-ties to a United Nations conference, was substantially modified in 1994 to satisfy U.S. objections regarding deep- seabed mining provisions, and is now recognized by 162 parties. In addition, Balton said U.S. acces-sion is supported by the entire U.S. mili-tary establishment, all major U.S. industries
involved with the oceans, and many other groups and individuals.
“Among the vast majority of nations in the world, this treaty is a well- accepted staple of international law with a long and noble lin-eage. But here in the United States, the con-vention has had a contentious history and still, amazingly to me, faces an uncertain future,” he said. “Only by joining the convention can the United States maximize legal certainty and have the best path to securing international recognition of our continental shelf.”
Noting that the United States is the world’s foremost maritime power, Rear Admiral Frederick Kenney Jr., judge advocate general and chief counsel for the U.S. Coast Guard, said the nation’s security is linked to free-dom of navigation, which the treaty would help to ensure. “We have more to gain from the legal certainty the [treaty] provides than any other country,” he said. “We need sub-stantive rules that ensure our access for mili-tary and commercial ships and aircraft vital to our security interests and our economy.”
Nations with coastlines automatically have a legally defined continental shelf that generally extends 200 nautical miles from the shoreline, Balton said. If some region
beyond those 200 miles meets certain cri-teria, nations also could receive exclusive rights to resources—including oil, gas, and minerals—on and under the seabed in an extended continental shelf (ECS) area. About 80 nations may be able to claim an ECS, and the United States might be able to claim an ECS that is 2 or more times the size of California, he said.
Although the United States is not yet a party to the convention, work is proceeding through the federal U.S. Extended Continen-tal Shelf Project to determine the potential size of an ECS, including collecting bathy-metric data to determine the foot of the slope of the continental shelf and seismic reflection data to determine sediment thick-ness, both of which are part of the formula to help decide a country’s maritime claim. Since 2003, the United States has conducted 33 cruises to gather the data and also has begun to analyze data that could be useful to support a U.S. claim to an ECS.
Balton said the data collection also has resulted in a number of ancillary scientific benefits including substantially filling in seis-mic data in the Arctic and elsewhere and locating some natural underwater features.
For more information, see http:// www .state .gov/ e/ oes/ lawofthesea/.
—RAndy ShowSTAck, Staff Writer
Editor’s note: AGU is a member of the Amer-ican Geosciences Institute, which in 2008 issued a document supporting ratification of the Law of the Sea Convention.
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similar to those that occur in nonvolcanic thun-derstorms. Redoubt’s plumes generally reached above 10 kilometers in altitude, similar to thun-derclouds, and contained abundant water and ice. Thus, contact electrification interactions among ice particles or ice- coated ash, water droplets, and supercooled ice pellets may also have played a role [Williams and McNutt, 2005].
Progress in Volcanic Lightning Research
The Mount Redoubt observations substan-tially extend the body of knowledge concern-ing volcanic lightning. The Mount St. Augus-tine lightning mapping observations, while being the first of their kind, were limited in that the instruments were installed after the eruption began, only two sensor stations were used, and the eruption itself was less energetic than that of Redoubt. The four sen-sors of the Redoubt study, on the other hand, recorded the entire eruption sequence and provided excellent two- dimensional observa-tions of the lightning activity. Obtaining fully three- dimensional observations will require
one or more sensors at locations closer to the volcano, which was not possible at the time for the Redoubt eruption. Progress toward this goal has been made using six- station lightning mapping measurements of the 2010 eruption of Eyjafjallajökull volcano in Iceland.
Acknowledgments
This research was funded by the U.S. National Science Foundation. We thank Harald Edens, William Rison, Graydon Aulich, and Sandra Kieft of New Mexico Tech and Edward Clark and John Paskievitch of the Alaska Volcano Observatory for their con-tributions to this project. We also thank the individuals and organizations who hosted our instruments on the Kenai Peninsula.
References
Behnke, S. A., R. J. Thomas, S. R. McNutt, D. J. Schneider, P. R. Krehbiel, W. Rison, and H. E. Edens (2012), Observations of volcanic lightning during the 2009 eruption of Redoubt volcano, J. Volcanol. Geotherm. Res., in press.
Brantley, S. R. (Ed.) (1990), The eruption of Redoubt volcano, Alaska, December 14, 1989 –August 31, 1990, U.S. Geol. Surv. Circ., 1061, 33 pp.
James, M. R., L. Wilson, S. J. Lane, J. S. Gilbert, T. A. Mather, R. G. Harrison, and R. S. Martin (2008), Electrical charging of volcanic plumes, Space Sci. Rev., 137(1-4), 399–418, doi:10.1007/ s11214 -008-9362-z.
Thomas, R. J., P. R. Krehbiel, W. Rison, S. J. Hunyady, W. P. Winn, T. Hamlin, and J. Harlin (2004), Accuracy of the Lightning Mapping Array, J. Geophys. Res., 109, D14207, doi:10.1029/ 2004JD004549.
Thomas, R. J., P. R. Krehbiel, W. Rison, H. E. Edens, G. D. Aulich, W. P. Winn, S. R. McNutt, G. Tytgat, and E. Clark (2007), Electrical activity during the 2006 Mount St. Augustine volcanic eruptions, Science, 315(5815), 1097, doi:10.1126/ science .1136091.
Williams, E. R., and S. R. McNutt (2005), Total water contents in volcanic eruption clouds and implications for electrification and lightning, in Recent Progress in Lightning Physics, edited by C. Pontikis, pp. 81–94, Res. Signpost, Trivandrum, India.
Author Information
Sonja A. Behnke, Ronald J. Thomas, and Paul R. Krehbiel, Langmuir Laboratory, New Mexico Insti-tute of Mining and Technology, Socorro; E-mail: sbehnke@ nmt .edu; and Stephen R. McNutt, Geo-physical Institute, University of Alaska Fairbanks
Spectacular Lightningcont. from page 193
NEWSU.S. Senate May Consider Law of the Sea Treaty Again
EOS_12042EOS_12042
CALLING ALL TEACHERS!Looking for innovative ways to teach K-12 students about tsunamis or the dangers of airborne volcanic ash?
We have ideas and tools for you. Check them out today at www.agu.org search keywords - 2011 GIFT Workshops.
Stream morphology data, primarily con-sisting of channel and floodplain geometry and bed material size measurements, his-torically have had a wide range of appli-cations and uses including culvert/ bridge design, rainfall- runoff modeling, flood inun-dation mapping (e.g., U.S. Federal Emer-gency Management Agency flood insur-ance studies), climate change studies, chan-nel stability/ sediment source investigations, navigation studies, habitat assessments, and landscape change research. The need for stream morphology data in the United States, and thus the quantity of data col-lected, has grown substantially over the past 2 decades because of the expanded inter-ests of resource management agencies in watershed management and restoration. The quantity of stream morphology data col-lected has also increased because of state-of-the-art technologies capable of rapidly collecting high- resolution data over large areas with heretofore unprecedented preci-sion. Despite increasing needs for and the expanding quantity of stream morphology data, neither common reporting standards nor a central data archive exist for storing and serving these often large and spatially
complex data sets. We are proposing an open- access data exchange for archiving and disseminating stream morphology data.
Development of common reporting stan-dards and a strategy for exchanging consis-tent stream morphology observations nation-ally is needed because recent data collection technologies (e.g., airborne and terrestrial lidar (light detection and ranging)) provide point-rich data sets in a variety of formats. More traditional survey data (e.g., cross- section geometries, longitudinal profiles, and bed material characteristics) are also being collected by a wider array of instrument types than in the past that provide large quantities of data in various formats (e.g., hydroacoustic multibeam echo sounders). Aggregating and serving these data across a common archi-tecture will increase their utility to the large variety of user groups in the public and pri-vate sectors. For example, there is a need to have physical channel characteristics geore-ferenced to digital stream networks (e.g., the National Hydrography Dataset) for modeling applications [Muste et al., 2010]. Standardized stream morphology data will also support tools such as the Consortium of Universities for the Advancement of Hydrologic Science,
Inc., Hydrologic Information System that inte-grates geospatial and observational data for rivers for the purposes of data discovery and access. Developing the data exchange in con-sultation with international standards organi-zations including the Open Geospatial Con-sortium through its Hydrology Domain Work-ing Group will offer opportunities to collabo-rate with related activities internationally and help ensure the broad adoption of stream morphology standards by government, aca-demic, and private sectors.
The Subcommittee on Sedimentation (SOS), a subcommittee of the Advisory Committee on Water Information, which promotes collaboration on sediment issues, formed a work group in 2009 to investigate development of a national stream morphol-ogy data exchange (NSMDE). The NSMDE work group members represent several fed-eral agencies and nonfederal organizations that collect and/or use stream morphol-ogy data (see http:// acwi .gov/ sos/ for more information about SOS and its member organizations).
Although the need and value of a NSMDE is clear to the work group members, its development presents many technical, logistical, and administrative challenges. To begin to address these challenges, the SOS work group sponsored a NSMDE workshop in April 2011 in Middleton, Wis., that explored three primary themes: data exchange scope, data exchange scale and potential data models, and administra-tion. A summary of the workshop, includ-ing recommendations to SOS for advanc-ing a NSMDE, is available at http:// acwi .gov/ sos/ sos _stream _morph _db _ workshopo _ summary _to _SOS _10 _13 _2011 .pdf. The full SOS resolved at its regular meeting in Octo-ber 2011 that the work group should con-tinue efforts to develop a NSMDE using the workshop recommendations as a guiding framework. Toward that end, the NSMDE work group has convened an ad hoc
subcommittee to identify and potentially implement specific actions to achieve a NSMDE as envisioned by workshop attend-ees. These efforts may be especially timely given recent related discussions in the geo-detic community about developing meta-data standards for terrestrial laser scanning (i.e., ground- based lidar) [Phillips et al., 2012].
Successful development and deploy-ment of a NSMDE will require the engage-ment of an interdisciplinary community. We recognize that the effort will only succeed if data submissions are easily facilitated, if data retrievals are user- friendly, and if data are served in a consensus format that is well documented and supports high- quality data. The SOS NSMDE work group wel-comes the participation of interested ecolo-gists, engineers, geomorphologists, data-base specialists, and end users to help make geomorphology data more available for a wide range of assessment, monitoring, and research activities and ultimately help the nation make better resource management decisions.
References
Muste, M., V. Merwade, D. Kim, D. Maidment, and T. Whiteaker (2010), Vision and progress: Data models for multi- dimensional representation of the river processes, J. Hydraul. Res., 48(4), suppl. 4, 58–59.
Phillips, D. A., J. S. Oldow, and J. D. Walker (2012), Outlining a strategic vision for terrestrial geodetic imaging, Eos Trans. AGU, 93(11), 121, doi:10.1029/ 2012EO110005.
—mAThiAS J. collinS, National Oceanic and Atmospheric Administration, Gloucester, Mass.; E-mail: mathias . collins@ noaa .gov; John R. GRAy, U.S. Geological Survey (USGS), Reston, Va.; mARie c. PePPleR and FAiTh A. FiTzPATRick, USGS, Middleton, Wis.; and JoSePh P. SchuBAueR- BeRiGAn, U.S. Envi-ronmental Protection Agency, Cincinnati, Ohio
The U.S. Earth Observing System “is begin-ning a rapid decline in capability as long- running missions end and key new missions are delayed, lost, or canceled,” according to a 2 May report by the U.S. National Research Council (NRC) titled Earth Science and Appli-cations From Space: A Midterm Assessment of NASA’s Implementation of the Decadal Survey.
By 2020 the number of NASA and National Oceanic and Atmospheric Administration (NOAA) Earth observing instruments in space is likely to decline to as little as 25% of the current number, a concern that rein-forces earlier studies that have warned that the U.S. system of environmental satellites is at risk of collapse, according to the report.
“The projected loss of observing capabil-ity will have profound consequences on sci-ence and society, from weather forecasting to responding to natural hazards,” said NRC committee chair Dennis Hartmann, profes-sor of atmospheric sciences at the University of Washington, Seattle.
The report does not include planned or proposed missions that are not yet funded. The report notes, though, that “even the most optimistic projected launch cadence
remains significantly below what would be required to prevent a major decline in NASA and NOAA’s orbiting space assets.”
The report is largely complimentary to NASA for responding “favorably and aggressively” to the decadal survey and for “embracing” its overall recommendations for Earth observations. “As a consequence, the science and applications communities have made significant progress over the past 5 years,” the report states.
A number of factors are blamed in the report for the potential Earth observing sys-tem crisis, including a budget profile that is insufficient to execute the recommended program of the decadal survey. “Congress’ failure to restore [NASA’s] Earth science budget to a $2 billion level is a principal rea-son for NASA’s inability to realize the mis-sion launch cadence recommended by the survey,” the report states. In addition, the report notes the need for a reliable and affordable medium- class launch capabil-ity and a national strategy from the White House Office of Science and Technology Pol-icy (OSTP) to establish and manage Earth observations from space.
Peter Colohan, senior policy analyst with OSTP, told Eos that “the president is strongly committed to science and technology and to ensuring a steady stream of Earth observation data in many of the domains the NRC has iden-tified. That is a difficult task given the overall budget challenge, but the administration is fully focused on these needs.” He said it is dif-ficult to characterize the overall state of the U.S. Earth observing system “in broad-brush statements. As the report itself points out, in certain areas we’ve had important success and in other areas we have some concerns.”
Colohan added that the Obama administra-tion has convened a National Earth Observa-tion Task Force under the National Science and Technology Council, which, he said, “soon will be releasing a National Earth Observation Strat-egy that begins to tackle this complex issue.”
Michael Freilich, Earth science divi-sion director for NASA, told Eos that the report “is a recognition of the fact that the on- orbit constellation that we have contin-ues to age, that the new desired measure-ments and missions have not been able to come on board because of a combination of budget shortfalls on the one hand, as [the report] point[s] out as a key impediment.” Freilich said another impediment has been recent launch failures of the Orbiting Carbon Observatory and the Glory mission, although other recent launches have succeeded.
He said that the basic point of the report’s concern about the state of Earth observing
systems is correct, but the approach the committee used to count instruments and missions does not include some mis-sions that are now moving forward and the report’s level of emphasis may not be cor-rect. “I would hesitate to use the word hys-teria, but perhaps they were overstating to make a case,” he said.
A report recommendation for a national policy on midrange launch vehicles is “spot on,” Freilich said, but he added that it will be decided at a level higher than the Earth science division. Freilich said he is taking seriously the recommendation to increase the frequency of NASA Earth Venture class low-cost competed missions, although there needs to be funding for that. In addi-tion, he said, the report’s recommendation for the Earth science division to implement its missions through a cost- constrained approach that balances capability, cost, risk, and schedule “is a strong endorsement of what we are already doing.” Regard-ing a report recommendation to establish an Earth system science and engineering team to advise NASA on the execution of decadal survey missions, Freilich said he is examining what is allowed and appropriate, given the agency’s current advisory com-mittee structure.
For more information, see http:// www .nap . edu/ catalog .php ? record _id =13405.
—RAndy ShowSTAck, Staff Writer
Newscont. from page 194
U.S. Earth Observing System Beginning a Rapid Decline, Report States
FORUMDeveloping a National Stream Morphology Data Exchange: Needs, Challenges, and Opportunities
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EOS_12058
NavigaTiNg graduaTe SchOOl aNd BeyONd:A Career Guide for Graduate Students and a Must Read for Every Advisor
Sundar A. Christopher
Graduate school can be an exciting and challenging time for students. This indispensable guide outlines the steps and skills necessary to succeed in graduate school and in your career. Dr. Christopher’s
“insider tips” also help students better understand their advisors, leading to more productive advisor/student relationships.
2011, 166 pp., softbound, ISBN 978-0-87590-736-9List Price $28.00
The Sulzman Award for Excellence in Education and Mentoring (Bio-geosciences section) recognizes AGU members who have sustained an active research career in a field related to bio-geosciences while excelling as teachers and serving as role models for the next generation of female scientists. This new award acknowledges the importance of female mentors in enhancing gender bal-ance in physical science career paths. The award is being endowed to honor Eliza-beth Sulzman, an isotope biogeochemist and soil scientist, whose enthusiasm for teaching awed many undergraduates at Oregon State University.
Current plans are to present the first Sulz-man award at the 2013 Fall Meeting. Appli-cants must be women who are within 15 years of receiving their Ph.D., and nomi-nation packages should include a cover let-ter, resumé, and three letters of recommen-dation. As they become available, more details will be posted on the Biogeosci-ences section Web site (http:// www .agu .org/ sections/ biogeo/). The award will provide up to $1000 to one successful nominee each year, although the exact monetary amount is yet to be determined. AGU is currently accepting donations to endow this award; contact Victoria Thompson ([email protected]) to get involved.
The Ivan I. Mueller Award for Distin-guished Service and Leadership (Geod-esy section) recognizes Ivan I. Mueller’s major contributions to international pro-grams that advanced geodesy over the past half century. The goal of this new annual award is to acknowledge major achieve-ments in service and/or leadership within the field of geodesy performed by an indi-vidual who is a member of AGU, who has primary or secondary membership in the Geodesy section, and whose body of work enhances the visibility of geodesy within AGU and other international associations.
This award encompasses all areas of geodesy, including exceptional performance in fieldwork, the development and mainte-nance of major software systems, leadership within scientific initiatives, education and public outreach, and a variety of other ser-vice and leadership achievements. Its pur-pose is to recognize achievements in the field of geodesy beyond pure scientific and research contributions. The deadline for nominations for the first Mueller award will be 15 March 2013, and the first presentation will occur at the 2013 Fall Meeting. More information, as it becomes available, will be posted at http:// www .agu .org/ sections/ geod-esy/ ivanimuelleraward .php.
With the advent of high- resolution spa-tial imaging, the idea of caves on other planets has moved from the pages of sci-ence fiction into the realm of hard-core science— complete with hypotheses, models, experiments, and observational data. Recently acquired data from space-craft, together with terrestrial analogs and numerical models, are providing new insights into caves on Earth as well as caves on other terrestrial planetary bodies (e.g., Moon, Mars, and Titan).
To address questions in planetary cave research, a workshop was organized to bring together terrestrial and planetary
researchers from diverse backgrounds with the goal of fostering collaborative interdisciplinary research. This workshop was sponsored by the Lunar and Plane-tary Institute (LPI) and NASA’s Jet Propul-sion Laboratory (JPL), organized by the U.S. Geological Survey (USGS) and the New Mexico Institute of Mining and Tech-nology, and hosted by the National Cave and Karst Research Institute and the U.S. National Park Service. Approximately 30 cave researchers and explorers, from North America, Europe, and Japan, had intensive discussions ranging from possi-ble astrobiological implications of caves to
the development of new approaches and technologies needed to detect, explore, and map extraterrestrial caves. The small group setting facilitated intensive discus-sion of problems and issues associated with cave processes on Earth, Mars, and Titan.
The summary of the workshop results and the consensus recommendations can be viewed as the ABCs of planetary cave research: astrobiology, biology and plan-etary protection, cave climates, detec-tion, exploration, formation mechanisms, near- surface geology, and human utiliza-tion. Caves are partially decoupled from the surface environment and therefore contain unique microclimates. Terres-trial cave microclimates often foster colo-nies of biota not found on the surface, and some cave- adapted species consume food sources that may be available in caves on other worlds. Terrestrial caves also pro-vide an opportunity to practice and test proposed planetary protection protocols, because caves are fragile environments. The detection and exploration of extrater-restrial caves require the development of new technologies and techniques, espe-cially in the areas of artificial intelligence
and subsurface communications. Caves on Earth form in many ways depending on the geological setting, e.g., lava tube caves from volcanic processes or limestone caves from aqueous processes. Caves on other worlds will likely form in many of the same ways as on Earth, but there may also be unique formation processes. Finally, caves on other worlds may some-day provide resources (e.g., water ice) or shelter for human explorers and colonists.
Workshop participants agreed that ter-restrial caves must be studied and pre-served. Caves provide unique microcli-mates with diverse biology that can be used to develop new technologies, test new protocols (e.g., planetary protection or robotic testing for life), and validate complex climate models.
A longer, more detailed version of this meeting report is available in the online supplement (http:// www .agu .org/ journals/ eo/ v093/ i020/ 2012EO200006/ 2012EO200006 _ suppl .pdf).
—TimoThy TiTuS, Astrogeology Science Center, U.S. Geological Survey, Flagstaff, Ariz.; E-mail: ttitus@ usgs .gov; and PeneloPe J. BoSTon, Department of Earth and Environmental Science, New Mexico Institute of Mining and Technology, Socorro
MEETINGInterdisciplinary Research Produces Results in the Understanding of Planetary CavesFirst International Planetary Cave Research Workshop: Implications for Astrobiology, Climate, Detection, and Exploration; Carlsbad, New Mexico, 25–28 October 2011
ABOUT AGUNewly Established AGU Awards and Lecture At its 5–6 April meeting, the AGU Honors and Recognition Committee approved the estab-lishment of the following section and focus group awards and lecture:
What’s on the Web?Read the latest offerings from the AGU Blogosphere:
Magma Cum Laude: “Bancroft (a pre-view)” (http://bit.ly/KNObnS)
Georneys: “Georneys with Dana—Part I: Dinosaur footprints near Holoyoke, MA” (http://bit.ly/LuXsUM)
GeoSpace: “Using science to disarm disas-ter” (http://bit.ly/IHWw9z)
The Landslide Blog: “Flash flood in Nepal kills at least 15, with up to 36 more missing” (http://bit.ly/KHwFzP)
Mountain Beltway: “Big old vesicles!” (http://bit.ly/J7AmnB)
Gas pockets in a lava flow in Owens Valley, California, from the Mountain Beltway blog.
Cal
lan
Ben
tley
About AGU cont. on next page
Volcanism and the AtmosphereSelfoss, Iceland
11–15 June 2012
REGISTRATION DEADLINE: 15 May 2012 (23:59 ET)
Volcanic eruptions can have a profound effect on the Earth’s atmosphere and environment on all time scales. From being the source
of most gases in the atmosphere over geologic time, to producing climate change detectable over the past millennia, to threatening aviation, volcanic eruptions provide a strong link between Earth’s activity
and its influence on the atmosphere and human history.
Eos: How did you begin teaching profes-sional development skills? How has your course evolved?
Christopher: The course I started 15 years ago had one goal: to teach students how to write proposals. Many students even-tually end up in careers that require pro-posal writing, and there is really nothing in the curriculum at most universities to pre-pare them. I picked NASA’s New Investigator Program as a template for the course, and the students had to write a proposal for that program.
Over the years I’ve listened to my col-leagues and my students, and I’ve added a lot of things to the class. Now they actually write a resumé or curriculum vitae; do some job hunting; and do a strengths, weaknesses, opportunity, and threats analysis. The class has evolved to include a lot of things, like time management and how to develop a pro-active style of managing your advisor, which is probably the most popular topic I cover. It has become a well-rounded career devel-opment course, and pretty much everything that I teach is in this book.
Eos: In your experience, what has been the most common stumbling block for
graduate students? How can they prepare for it?
Christopher: I think a lot of students, not all of them but many, come to a uni-versity thinking that an advisor is going to help them with all aspects of their career, that they’re going to help the student write papers and proposals and help them with the job search. So I’d say that many stu-dents are really looking for a mentor, not just an advisor. An advisor is someone who is interested in the student’s academic path; they tell them which courses to take and show them the nuts and bolts of how to do research. A mentor is more interested in the student’s career, even after the student grad-uates. When a student comes into a graduate program looking for a mentor, not an advi-sor, he or she can get disillusioned when there is a mismatch between the advisor’s and the student’s expectations. Not all advi-sors want to be mentors, and there is noth-ing wrong with that. But I think this expec-tation mismatch leads to a lot of conflict. Therefore, I tell the students, learn how to manage your advisor.
Eos: What do you mean by “manage your advisor”?
Christopher: Learn your advisor’s rhythms; put yourself in his or her shoes. Case in point: Let’s say that as a new graduate student, you have a young advisor who is just starting his career as an assistant professor. That means that you need to think, “Okay, maybe my advi-sor is nervous about tenure or about getting a promotion, and maybe he is writing a lot of grant and contract proposals.” As a student, you need to know the number of classes he teaches and the other demands on his time.
It’s tricky, because students tend to think that their advisor knows best, that their
advisor is going to initiate meetings and help them with their career. A lot of times that doesn’t happen because advisors are man-aging their own lives, going through their tenure process, and climbing their own career ladder. So if your advisor is typically late for, or avoids, meetings, what do you do?
I tell my students to proactively manage their advisors. I tell students to be in the driv-er’s seat: Initiate meetings, put together pro-grams of study that the advisor can review
Beginning his scientific career as an engineering student at PSG College of Technology, in Coimbatore, India, Sundar A. Christopher has negotiated and navigated the higher-educa-tion system to become the chairman of the Department of Atmospheric Sciences at the Uni-versity of Alabama in Huntsville. Drawing on his own experiences and on insights gleaned from the students who have passed through his graduate-level professional development course, Christopher takes a lighthearted look at peer review, proposal writing, manag-ing budgets, and making the most of conferences in the AGU book Navigating Graduate School and Beyond: A Career Guide for Graduate Students and a Must Read for Every Advisor. In this interview, Eos speaks to Christopher about overcoming the bureaucratic, logistical, and personal hurdles that too often lead students to disillusionment and conflict.
The Ronald Greeley Early Career Award in Planetary Sciences (Planetary Sciences section) is being awarded in 2012 for the first time. The annual award hon-ors Ronald Greeley, beloved colleague and active planetary scientist, who passed away in late 2011. Ron mentored or influenced a large fraction of the planetary scientists working today, and naming this early-career award for him is a fitting way to honor his legacy. Nominees must be a member or an affiliate of the Planetary Sciences section of AGU and must be within 6 years of receiv-ing their Ph.D. on the first day of the year in which the award is to be made (e.g., nomi-nees must have earned their doctorate on or after 1 January 2006 to be eligible for the 2012 award). Parental leave, if provided by the candidate’s institution and taken by
the nominee during this 6-year period, can extend the 6-year period.
Nominations, which should include a cover letter, resumé, list of selected pub-lished papers, and at least three letters of support, need to be submitted to Phil Christensen by 15 July, either by post or by e-mail (phil .christensen@ asu .edu). For more detailed instructions and the postal address to which hard copies of documents can be sent, see http:// www .agu .org/ sections/ plan-ets/ about .php #greeleyaward.
The Leptoukh Lecture (Earth and Space Science Informatics Focus Group) recog-nizes advances in data management and analy-sis, large-scale computation and modeling, and hardware and software infrastructure—issues that profoundly affect the research capabilities of all AGU disciplines. Named in honor of the late Greg Leptoukh, a pioneer in satellite data quality and provenance, the Leptoukh Lecture aims to identify and support achievements in computational and data sciences.
The first lecture, which will be given at AGU’s 2012 Fall Meeting, will discuss Lep-toukh’s contributions; subsequent lectures for this annual honor will be given by an AGU member selected by an awards com-mittee. This member must have Earth and Space Science Informatics as his or her first or second affiliation. Nomination packages, which should include a cover letter, resumé, and two letters of support, will be accepted between 1 January and 1 April 2013 for next year’s award; more details, as they become available, will be posted at http:// essi .agu .org.
The Atmospheric Sciences Ascent Award (Atmospheric Sciences section) aims to reward exceptional midcareer sci-entists in the fields of the atmospheric and climate sciences. Scientists can be from aca-demia, the government, or the private sec-tor; “midcareer” is defined here as between 8 and 20 years post-Ph.D. or the scientist’s highest degree. Candidates must demon-strate excellence in research and leadership
in their field. Nominations for women and underrepresented minorities are encour-aged. It is anticipated that up to four awards will be made each year; each winner will receive a certificate and a $1000 check.
Nominations packages for the Ascent Awards should contain an up-to-date resumé no longer than two pages in length and a bib-liography not exceeding three pages. A nomi-nation letter should be accompanied by up to three supporting letters, each no longer than two pages. To be considered for awards given at the 2012 Fall Meeting, the complete nomination package should be sent to Peter J. Webster (pjw@ eas .gatech .edu), chair of the Ascent Award committee, by 1 July 2012. As they become available, more details will be posted on the Atmospheric Sciences Web site (http://www.agu.org/sections/atmos/).
—BeTh PARedeS, Assistant Director, Executive Operations and Awards Administration, AGU; and mohi kumAR, Staff Writer
About AGUcont. from page 196
AGU BookshelfNavigating Graduate School and Beyond: A Career Guide for Graduate Students and a Must Read for Every Advisor
and approve, put your schedule together for when you want to take your exams. Every-thing should be proactive rather than wait-ing for your advisor to say, “Why don’t you write a paper in this area, or do this or that?”
Eos: How can being career focused, instead of class or grade focused, help a graduate student focus his or her time and energy?
Christopher: In the book I use the sow-ing and reaping paradigm; you really have to give some thought to where you’re going and where you want to be. Ideas change, and I realize that—I used to be an engineer, and here I am with a Ph.D. in atmospheric sci-ence. But at the same time, I really encour-age students to set aside a bit of time each week to think about where they want to end up, either as a professor or a researcher for a large institution or center, or in some other position. Once they have locked on to that, I think it is a little bit easier for them to start thinking about what they will need to get there.
In higher education, for example, you’re going to be evaluated on teaching, research, and service. This means you need to work on developing a teaching portfolio while you are in graduate school. Research, too, is very competitive. If you write grants as part of your graduate school experience, it would be a huge benefit. So I think really knowing where you want to be, and work-ing really hard at it, is critical. Otherwise it just becomes taking classes for the sake of taking classes. I’m pretty blunt when I tell my students that a Ph.D. is not really an academic degree; it’s a research degree. Your papers count, your research counts. The number and the quality of papers that you publish while you are part of graduate school are going to make your curriculum vitae stand out.
Eos: One section of the book stands out as both rebellious and obvious. Can you explain your method for “ditching the dissertation”?
Christopher: I do not recommend that students write a formal dissertation, and I have many reasons why. A typical disser-tation is written like this: The student sits down and writes 100, 200, 300, however
many hundreds of pages. Then draft 1 goes to his advisor, then draft 2, draft 3. He works on it for several months, and then the student sends it to his committee. Then there are more revisions. Finally, the stu-dent stands up and defends his dissertation. At the end of it all, after he’s received his degree, he sits down and thinks, “Ah, now I have to write a paper.” This leads to the task of slicing and dicing that many-hundred-page dissertation into 10- to 20-page papers that meet a journal’s requirements. You’ll need to change the tone of your writing, the figures, and some of the contents, so you’ve actually doubled your work. You’ve done a formal dissertation—which nobody ever reads, by the way—but you have so much more work to do.
So instead of this formal dissertation pro-cess, I recommend my students take a dif-ferent approach. I suggest that they write two or three peer-reviewed papers. After they write these papers, the process is, basi-cally, to write a very short introduction that says, “My dissertation is organized into two major sections.” Then, they slide the entire peer-reviewed paper in as part 1 and the next paper as part 2. They write a very short future work or conclusions section and, if they have another paper, add it as an appen-dix and call it quits. This works on many fronts, because think about this: On the day of his defense, the student stands up to give his presentation. On the first slide is the title of his research. On the second slide is the list of papers that he’s already published. At that point, if the committee members knew what was going on, they would say, “Where do I sign the dotted line?” And why is that? Because the peer-review process typically puts papers in the hands of reviewers who are experts in that particular topical area. The thesis work has already been vetted by the international committee, which should make it easy for the thesis committee to also approve the work.
Seaming a dissertation together after you’ve written your papers means you have to do the work only once. It lets the larger research community know about your work, and, finally, peer-reviewed
papers are what typically count in the geosciences. So it works well for every-one involved to reduce the time and the frustration.
Eos: Recurring themes in the book are those of taking ownership and of becoming a resource center. What do you mean by this?
Christopher: There is a definite link between lack of ownership and lack of productivity. When a student first joins a research group, there is a short period of time in which the advisor and the student are working together and the student sees the project that they are working on as “his advisor’s project.” With time and proper mentoring, the advisor should be able to hand over the project to the student. So what do I mean by that? The student should always think about going the extra mile in terms of doing research analysis, producing plots or figures, writing papers, and being part of the team. It doesn’t happen over-night, but eventually there needs to be a transition during which the student starts to think of the project not as his advisor’s pro-ject but as his own dissertation and his own research project.
As part of smoothing and enabling this tran-sition, I think that becoming a resource center is really critical, especially considering the fast pace of research. In my graduate school days I had to set up weekly meetings with my advisor, or maybe send the occasional e-mail with figures or plots or analysis. I tell my stu-dents not to do this. I tell them, “Well, you can design a blog or a Web site that says, ‘These
are the papers that I have read, and here are some figures and plots.’” As a student, you become a resource for your advisor for that particular topical area. This lets your advisor keep up with what you are working on without needing that weekly check-in, but above that, becoming a resource center also builds ave-nues for collaboration with the wider scientific community.
Eos: Since you started teaching career counseling, have the infrastructure and sup-port being offered to graduate students and recent graduates improved?
Christopher: I think that there has been an increase in awareness of these issues. I’m not saying my book brought about that change, but at least in the places to which I have traveled there has been an increased aware-ness of how this could help students and even-tually help the faculty, the department, and the university as a whole. I think we want our stu-dents to succeed and not to get disillusioned by the myriad things that can get in their way. I don’t have numbers for how resources in this area have changed, but I can say that I have personally been given freedom to expand my course to all of the graduate students at my university, rather than just offering it to the Department of Atmospheric Sciences. So I think it is catching on.
2011, vii + 157 pages, ISBN 978-0-87590- 736-9, AGU Code SP0647369. List Price $28, AGU Member Price $20.
—colin SchulTz, Writer
POSITIONS AVAILABLE
Geochemistry
Postdoctoral Researcher: Secondary Ion Mass Spectrometry (SIMS) Microprobe Analysis.
The Lunar and Planetary Institute (LPI), part of the Universities Space Research Association, invites applications for a postdoctoral fellowship in the area of SIMS isotopic and elemental analysis of Martian meteorites.
The successful candidate will work as part of an international team at NASA Johnson Space Center in Houston, Texas. The candidate should be self-motivated, and must have a Ph.D. in geochem-istry, cosmochemistry, or a related field. A strong background in ion microprobe analysis is essential. Experience in the analysis and interpretation of Pb isotopes will be considered highly advantageous. Experience with a Cameca 1270/80 will also be considered advantageous. Knowledge of Martian geochemistry and petrology will be considered beneficial, but not essential. Significant travel will be required of the successful candidate. Candi-dates should also present an independent research plan that complements the Martian meteorite study. Some analytical development using the Johnson Space Center Cameca NanoSIMS may be required.
The position would be for one year, with pos-sible extension to a second year. Applicants should send a letter of interest, a curriculum vita with a
list of publications, a brief (maximum three pages) statement of research interests, and a list of three references to [email protected]. Review of can-didates will begin immediately. For further details, contact either Justin Simon ([email protected]) or John Jones ([email protected]). Fur-ther information on current research and facilities at the LPI can be found on our website www.lpi.usra.edu. Information on JSC facilities and labora-tories can be found at http://ares.jsc.nasa.gov/ares/index.cfm.
The Universities Space Research Association is an Equal Opportunity Employer.
Solid Earth Geophysics
Faculty position in Structural Geology-Active Tectonics.
The Department of Geology & Geophysics at the University of Utah invites applications for a tenure-track faculty position in structural geology and/or active tectonics available as early as spring semester 2013. We anticipate hiring at the Assistant Professor level but will consider exceptional can-didates at the Associate Professor level. Applicants must have a Ph.D., and the successful candidate is expected to build a productive and internationally visible research program. Expertise in structural geology is desirable but a broad range of field-oriented tectonic specialties will be considered.
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AGU Bookshelfcont. from page 197
A word cloud covering the themes of time and stress management, research productivity, and the student-advisor relationship. These terms exemplify Sundar A. Christopher’s advice for navigating graduate school and early-career science.
CLASSIFIEDADVERTISING INFORMATION
Eos is published every Tuesday, except the last week of December. For a classified or display adver-tisement to be published in a future issue of Eos, electronic copy must reach us by 23:59 eastern time, 9 days prior (Sunday) to publication, except around certain holidays, which have earlier dead-lines. No cancellations accepted after deadline.
AGU does not verify claims made or compliance with laws in advertisement appearing in Eos. Nei-ther Eos, the American Geophysical Union, nor its directors, offices, employees, agents, or members can be held liable for content of the advertisements. AGU does not endorse or approve the content of any advertisement.
For inquiries on advertising pricing and availability:
For further details and to apply, please go to: http://utah.peopleadmin.com/postings/13949.
The University of Utah is an Equal Opportunity/Affirmative Action employer and educator. Minori-ties, women, and persons with disabilities are strongly encouraged to apply. Veterans preference. Reasonable accommodations provided. For addi-tional information:http://www.regulations.utah.edu/humanResources/5-106.html.
The University of Utah values candidates who have experience working in settings with students from diverse backgrounds, and possess a strong commitment to improving access to higher educa-tion for historically underrepresented students.
The University of Chicago Research Beamline Scientist Position Posting.Summary:The University of Chicago Center for Advanced
Radiation Sources (CARS) is seeking a Research Beamline Scientist to become part of the Geo-SoilEnviroCARS (GSECARS) research facility at the Advanced Photon Source (APS) located at Argonne National Laboratory (ANL). The success-ful candidate will provide support for scientific users from the multianvil high pressure commu-nity who conduct research using the GSECARS synchrotron beamlines at the APS. The Research Beamline Scientist will participate in core and collaborative research and will be involved in the development of new techniques for collection and analysis of synchrotron data, as well as in the maintenance and development of beamline instrumentation.
A Ph.D. in Geology, Physics, or related field is required along with a minimum of three years syn-chrotron research experience using large-volume press (LVP) techniques. Ability to work as a team member and independently is required as are good organization skills, excellent verbal and written communication skills and relevant computer skills. In addition, the ability to work in an environment with strict safety regulations and satisfy the require-ments for access to Argonne National Laboratory is essential for consideration for this position.
Position Responsibilities:1). Assist the user community in using the LVP
facilities. 2). Core and collaborative research using high pressure techniques. 3).Participate in the development of new techniques and instrumenta-tion for improving the quality of synchrotron data.
All interested candidates must apply through the University of Chicago’s Jobs web-site: https://jobopportunities.uchicago.edu/applicants/jsp/shared/position/JobDetails_css.jsp?postingId=558722. All information requested in the job posting must be completed to ensure review of any application. Qualified candidates will be contacted to arrange interviews; reference letter submission information will be provided for
qualified applicants. The University of Chicago is an Affirmative Action/Equal Opportunity Employer.
Senior Lectureship in Exploration Geophysics, at the University of Edinburgh, UK.
Grade: UE09: £46,846-£52,706Applications are invited for a Senior Lecture-
ship in the area of Exploration Geophysics. You will have an exceptional track record of delivering world-class exploration geophysical research. You will join one of the largest groups of exploration-related academic staff in Europe, working on a variety of problems in exploring and monitoring hydrocarbons, waters, ores, and stored waste in the Earth’s subsurface (http://www.geos.ed.ac.uk/seismic). You will be known internationally for your exploration-related research and must have practi-cal experience of processing (probably industrial) seismic data sets, and will be able to demonstrate related teaching experience. You will have a strong interest to lead the direction of exploration teach-ing at postgraduate Masters level and will be an important contributor to teaching of seismic data processing and imaging at undergraduate and post-graduate level.
This is an open-ended permanent post from September 2012.
Deadline for applications: 31 May 2012.Applications can be made through the Univer-
The School of GeoSciences at the University of Edinburgh, UK, Senior Lectureship in Struc-tural Geology.
Grade: UE09: £46,846-£52,706Applications are invited for a Senior Lecture-
ship in the area of Structural Geology. You will have a track record of delivering outstanding interdisciplinary and applied research founded on the observation, analysis and interpretation of structures and rock fabrics in the Earth using Geological, Geophysical and/or Geochemical data. You will be expected to develop an excellent programme of applied structural research that is relevant to Earth Science problems in energy, Earth resources, and the environment. Example areas of application might include natural hazards, the extraction of groundwater, shale gas, coalbed meth-ane, ores and minerals, oil and gas from carbonate and siliciclastic reservoirs, exploitation of deep geothermal heat, or the geological disposal of CO2, or toxic or nuclear waste. You will have demon-strable relevant teaching experience. You will lead delivery of undergraduate courses in structural and field geology, deliver teaching on related Earth Sci-ence undergraduate courses, and contribute to the
delivery of postgraduate Masters programmes (e.g. in Applied Geology, Carbon Capture and Storage, Exploration Geophysics).
This is an open-ended permanent post from 01 August 2012.
Deadline for applications: 31 May 2012.Applications can be made through the Univer-
Staff Position, Institute for Rock Magnetism.The Institute for Rock Magnetism (IRM) is a
national multi-user facility funded by NSF for stud-ies in rock/paleo/geo magnetism. IRM staff mem-bers interact with visiting scientists from around the world, helping them use the facility effectively for a wide range of geological and geophysical investiga-tions. We are looking for an individual who is self-motivated, can take on a range of responsibilities, and work independently of close supervision. The position involves participating with IRM faculty and staff in the management and supervision of facility operations, including instrument maintenance and software development as well as direct interaction with visiting researchers (80%), and carrying out independent research (20%).
For additional information, visit www.irm.umn.edu or contact [email protected]. Review of applications will begin on June 30 2012. To sub-mit an application, go to http://www.geo.umn.edu/dept/positions/Search.html (requisition # 172658 or 175602). The University of Minnesota is committed to the policy that all persons shall have equal access to its programs, facilities, and employment without regard to race, color, religion, national origin, sex, age, marital status, disability, public assistance status, veteran status or sexual orientation.
Space Physics
Research Scientist Solar Observatory - Solar Physics
Brailsford College of Arts & Sciences.Prairie View Solar Observatory (PVSO) invites
applications for the position of Research Scientist. The position will operate and manage PVSO’s observational facilities, conduct solar physics research, and organize and guide various solar observation-related scientific and educational activ-ities, including students’ research practice and fac-ulty’s site teaching at the observatory. The success-ful candidate will be expected to assist the Director of PVSO in acquiring outside research/education funds to support the observatory’s instrumentation development and the Prairie View A&M Univer-sity’s students in participation of PVSO’s research activities. Doctorate Degree or Ph.D. in Physics or Astronomy and seven or more years of solar phys-ics and space physics related experience. Ability to perform maintenance of telescope and dome systems; ability to conduct solar and space science
related research, and ability to train students in the related job. To review the job announcement in its entirety and to apply online, please visit us at: jobs.pvamu.edu. For assistance with the online applica-tion process, please contact the Office of Human Resources at 936-261-1730 or [email protected]. Questions related to PVSO or the position directly can be directed to Ms. Karen Bostwick at 936-261-2680 or [email protected].
Prairie View A&M University is an Affirmative Action/Equal Opportunity Employer
Interdisciplinary/Other
POSTDOCTORAL RESEARCH SCIENTIST ENVIRONMENTAL SCIENCES PH.D. PROGRAMCOLLEGE OF SCIENCES AND HUMANITIESBALL STATE UNIVERSITYMUNCIE, INDIANA.Professional contract position available July
1, 2012 Responsibilities: conduct interdisciplin-ary environmental research associated with the Environmental Sciences Ph.D. Program; provide support with field and laboratory activities; develop manuscripts for publication; present research at local and national scientific venues; participate in activities of the Environmental Sciences Ph.D. program. Minimum qualifications: Ph.D. in chem-istry, geology, biology, environmental sciences, or a related scientific field; experience in environmental research. Preferred qualification: presentation and publication of previous research.
Send cover letter, curriculum vitae, transcripts, and the names and contact information for three references to: Professor E. Michael Perdue, Envi-ronmental Sciences Ph.D. Program, Ball State University, Muncie, IN 47306 or to [email protected].. Review of applications will begin May 15, 2012, and will continue until the position is filled. (www.bsu.edu)
The Environmental Sciences Ph.D. Program seeks to attract an active, culturally and academi-cally diverse staff of the highest caliber. Ball State University is an equal opportunity, affirmative action employer and is strongly and actively com-mitted to diversity within its community.
The department of Physics at Angelo State University is seeking qualified candidates for an Instructor of Geosciences position to begin August 2012. The successful candidate will teach undergraduate introductory and upper-level lecture and laboratory sections in Geology and Physical Science. Research and teaching field areas nearby include Permian basin, Llano uplift, and exposures in West Texas, northern Mexico, and eastern New Mexico containing Laramide and Basin and Range structures.
Candidates must have an aptitude in and potential for excellence in undergraduate teach-ing in the classroom and in the field. Ability to enhance teaching using appropriate technologies
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Eos volume 93 number 20 15 may 2012
is desirable. Masters Degree in Geology or related field from a regionally accredited institution required. To apply online, please visit http://www.angelo.edu/publications/employment/
Angelo State University, part of the Texas Tech University system, enrolls 7000 students and is a His-panic Serving Institution. The Department of Physics emphasizes undergraduate education. The department currently enrolls over sixty majors in Geoscience and over 30 minors in Earth Science. Approximately 150 students major in Physics. See more department details at http://www.angelo.edu/dept/physics/
US Geological Survey, Program Coordinator, Volcano Hazards Program.
The U.S. Geological Survey (USGS) invites appli-cations for the position of Program Coordinator, Vol-cano Hazards Program, in Reston, VA. This Program has both domestic and international responsibilities and works closely with Federal, State, local and private-sector partners to ensure that hazards infor-mation and warnings are understood and effectively integrated into response plans and hazard mitigation and crisis response actions. The Program Coordi-nator plans, develops, and implements all volcano hazards activities and provides scientific leadership and funding guidance for these activities, which include maintaining the U.S. volcano monitoring network system, conducting fundamental research into volcanic processes, issuing hazard assessments and warnings, and working with responsible emer-gency and land management partners, as well as
other affected public and private-sector groups (e.g., civilian and military air route authorities) on crisis response and aircraft/airport ash hazard response plans. The Incumbent facilitates the collaboration of activities relating to volcano hazards and their effects across the Bureau, including coordination for implementation, reporting, and leveraging of both funding and expertise.
This is an interdisciplinary position that may be filled as either Geologist, GS-1350-15; Geophysi-cist, GS-1313-15; or Hydrologist, GS-1315-15. It is a full-time, permanent position and has a salary range of $123,758 to $155,500 commensurate with experience. The following announcement is open to all U.S. Citizens: ATL-2012-0434. The following announcement is open to all U.S.Citizens that are current or former Federal employees: ATL-2012-0435. Announcements are open from May 7 to June 11, 2012. Details are available at: http://www.usajobs.opm.gov. U.S. Citizenship is required. Con-tact: Office of Personnel 703-648-7296 or [email protected]. The U.S. Geological Survey is an equal opportunity employer.
SERVICES, SUPPLIES, COURSES, & ANNOUNCEMENTS
United States Polar Rock Repository. Rock samples are available as no-cost loans for research, teaching & museum use.
http://bprc.ou.edu/emuwebusprr.
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Simulating thermokarst lakes
Thermokarst lakes, which form from thawing permafrost, alter landscapes and hydrology and can release significant amounts of methane to the atmosphere. To learn more about the dynamics of thermo-karst lakes, Kessler et al. created a three- dimensional numerical model of these lakes that includes the surrounding topog-raphy. They simulated 10,000 years of evo-lution of two small thermokarst lakes on the northern Seward Peninsula in Alaska and studied the pattern of methane pro-duction and emission over time. They found that the rate of methane produc-tion depends on the rate of expansion of thermokarst lakes into ancient permafrost and that local topography strongly influ-ences the rate of expansion and drain-age of the lakes. One lake, located in rel-atively flat surroundings, expanded rap-idly and drained many times, while the other, surrounded by steeper slopes, grew more slowly and drained only partially. Thus, topography is an important con-trol on thermokarst lake dynamics and methane emission. (Journal of Geophysi-cal Research- Biogeosciences, doi:10.1029/ 2011JG001796, 2012) —EB
Silicic acid biogeochemistry in the Gulf of California
Silicon is an essential nutrient for the growth of siliceous phytoplankton, which accounts for a significant amount of marine primary production. Con-straints on silicic acid limit primary pro-duction and carbon export, so biogeo-chemical silicon cycling influences the carbon cycle and climate. Silicon cycling has been studied mostly in iron-limited
regions of the ocean, and not much is known about the effects of iron avail-ability on silicon cycling in coastal upwelling systems. Pichevin et al. inves-tigated nutrient profiles and sedimen-tary records from the Gulf of Califor-nia, which is not limited by iron year-round. They found that iron limitation even in this type of setting is an impor-tant factor in silicon cycling in coastal upwelling regions. ( Paleoceanography, doi:10.1029/2011PA002237, 2012) —EB
Satellite tracks seasonal changes in atmospheric heavy water
From 10 to 30 kilometers in altitude, the steadily decreasing temperatures in the upper troposphere and lower stratopshere cause water vapor containing the hydro-gen isotope deuterium— HDO, or heavy water— to preferentially condense out of the air, falling back toward the surface as ice. This selective depletion of heavy water leads, in theory, to a 90% drop in the ratio of heavy water to regular water vapor concentrations as compared to sur-face levels. The observational record, however, does not always align so well with theoretical predictions. Research-ers suspect that skewed heavy water con-centrations are due to atmospheric mix-ing, where deuterium- laden water from lower altitudes is transported upward. By tracking changes in the HDO/H2O ratio, researchers hope to tease out the his-tory of evaporation, condensation, and convection that affect a particular atmo-spheric region.
Using a detector aboard the Canadian Space Agency’s SCISAT-1 satellite, Ran-del et al. identified a number of regular features of the global atmospheric heavy
water vapor distribution, including consis-tent patterns of seasonal variability.
Using a technique known as solar occultation, whereby the detector looked through the Earth’s atmosphere at the Sun, the authors collected 24,000 atmospheric composition measurements from 2004 to 2009. They found that, in general, the HDO/H2O ratio is at a minimum near 15 kilo-meters in altitude. During the summer and winter months they found an enhanced minimum in the subtropics of the cur-rent winter hemisphere. In the spring and fall the strongest minimum lay nearer the
equator. Further, the authors identified a regionally sensitive relationship between atmospheric deep convection and heavy water concentrations, with atmospheric mixing associated with the North Ameri-can monsoon tied to elevated stratospheric HDO/H2O ratios and depressed heavy water concentrations from deep convection in Asian- Pacific regions. (Journal of Geo-physical Research- Atmospheres, doi:10.1029/ 2011JD016632, 2012) —CS
—eRnie BAlceRAk, Staff Writer, and colin SchulTz, Writer
Hydrologic pulses, temporary increases in water inputs such as bouts of precipitation, can affect biogeochemi-cal processes in ecosystems by provid-ing water and nutrient resources. How-ever, ecosystem responses to the water vary. Harms and Grimm conducted experiments to determine how hydro-logic pulses and existing moisture con-ditions interact to affect the biogeo-chemistry of desert floodplains. Dur-ing dry and monsoon seasons at their study site in the floodplains of the San Pedro River in Arizona, the researchers experimentally added pulses of water and then measured emissions of several trace gases that are indicators of biologi-cal processes. They found that the size of the added hydrologic pulse strongly interacted with existing soil moisture conditions in determining emissions of some trace gases. For instance, follow-ing dry conditions, pulses of water stim-ulated carbon dioxide, methane, and nitric oxide emissions, with larger water
pulses stimulating more emissions. How-ever, when soil was already wet, the addition of water pulses had less effect on the emission of these gases. (Journal of Geophysical Research-Biogeosciences, doi:10.1029/2011JG001775, 2012) —EB
Measuring biogeochemical responses to pulses of water
Floodplain of the San Pedro River in Arizona during a flood. The timing and size of water inputs, including floods and precipitation, influence the flux of trace gases from flood-plain soils.
