• Radar Altimeter Data Base System (RADS) -- producing a consistent set of climate-grade observations spanning multiple satellite missions

• Altimeter/Tide Gauge calibration project

• Re-analysis of altimetric record -- connecting GEOSAT to TOPEX

• Historical analysis from tide gauge & hydrographic observations

• Preparing for Jason-2/OSTM (2008 launch) … Four Party Mission NASA/CNES with NOAA & EUMETSAT junior partners

• Planning/Gaining Approval for Jason-3 (2013) … NOAA & EUMETSAT Proposed Lead Agencies.

NOAA Lab for Satellite Altimetry Global Sea Level Rise R&D Program

Global Sea Level Rise From Topex & Jason-1 Compared With Tide Gauge Rates From 1870-1930 and the 20th Century

TOPEX

3.0 mm/yr 1993-2006

JASON-1

~1.0 mm/yr 1870-1930

1.7 mm/yr 20th century

Mult-Mission Global Sea Level Rise From RADS

Global mean sea level based on a simultaneous fit to a single trend and annual function and separate bias estimates for each satellite.

Global Sea Level Trends From Multiple Altimeters Can We Control the Errors?

Difference in GSL trends

(Topex+Jason) - (Envisat+ERS2+ERS1)

Probably a Reference Frame Problem!

ALT TideGaugeNOAA Altimeter/Tide Gauge Calibration Project

• No coherent national or international program at present. Pacific gauge network funded by NOAA/OCO

• NOAA now funding Gary Mitchum (Univ. South Florida) to produce and run a NOAA operational web-based system

• Tide gauge calibration only way of determining bias & drift errors.

• May provide answer to “gappy” record problem.

14 cm bias error+/-0.4 mm/yr drift error

Argo Profiles of Ocean Heat Content vs. GSLR From Altimetry

Sea level continued to rise despite cooling and decrease in thermosteric sea level

~ 6 mm drop in thermosteric sea level

From Lyman et al., GRL, 2006

NOAA GLSR Web Site Under Development

•Building on Univ. of Colorado site developed by Eric Leuliette -- new LSA hire.

•Multi-satellite based on RADS (Remko Scharroo)

•Monthly Tide Gauge Calibration (Univ. of South Florida with R20 support) -- tied to OCO support of tide gauge network.

Extending the TOPEX/Jason Global Mean Sea Level Time Series with GEOSAT ObservationsLaury Miller, Remko Scharroo, John Kuhn, Caroline Harbitz

Using tide gauge records that span the gap between GEOSAT & TOPEX to determine (1) GEOSAT trend errors, (2) GEOSAT bias with respect to TOPEX.

If we succeed, we’ll lengthen the altimetric global sea level record by 45%

Before Correcting Trend Error After Correcting Trend Error

Gyre-scale Atmospheric Pressure Variations and their Relationship to 19th and 20th Century Sea Level Rise

Laury Miller & Bruce C. Douglas

Church & White (2006) identified an acceleration in Global Sea Level Rise (GSLR) centered on 1920-1930.

Figure 1. Global mean sea level from the 1870-2002 reconstruction by Church & White (2006), A 20th century acceleration in global sea-level rise, GRL, 33, L01602. Monthly global average (lower curve); yearly global average with quadratic fit (middle curve); yearly global average with satellite altimeter data superimposed (upper curve).

Here we show that this behavior is closely related to long-term, gyre-scale surface pressure variations similar to the Northern Annular Mode (Arctic Oscillation) and not global mass or volume change.

-20

-15

-10

-5

0

5

10

15

20

2002 2002.5 2003 2003.5 2004 2004.5 2005

Altimetry – stericGRACE

Global Ocean

• Sea level rise is a combination of thermal expansion and additional water from continental sources (e.g. glaciers).

• Eric Leuliette has exploited altimetry, in situ measurements of thermosteric changes in sea level, and mass changes inferred from NASA’s GRACE gravity mission in an effort to close the sea level change budget.

Using GRACE to identifying cause(s) of GSRL GRACE(mass) = ALT(mass+vol) - Argo(vol)

In orbit Approved Planned/Pending Approval

97 98 99 00 01 02 03 04 05 06 07 08 09 10 11 12

2-f MR & 66-deg, 10-day, 315-km

98-deg, 35-day, 80-km – failure of on-board recording

ERS-2

ENVISAT

JASON

13 14 15

Sentinel 3 – 3-sat series

Jason

108-deg, 17-day, 160-km

Jason-3

AltiKa on SARAL

TOPEX-Poseidon

Altimeter Missions

GEOSAT Follow-on

OSTM (Jason-2)

HY-2 series

SWOT

Timely data access?

NOAA’s Expanding Role In Satellite Altimetry

Jason-2/OSTM --- Launch 2008

NASA/CNES with NOAA/EUMETSAT junior partners

NOAA Responsible for ground system -- controlling satellite, downlinking data, near-real time data processing, archive (CLASS) and distribution

Jason-3 --- Proposed launch 2013

NOAA & EUMETSAT lead agencies, with CNES and possibly NASA participation.

Need to secure funding -- NOAA’s share $150M over 5 years?