Remote Sensing of (Alaskan boreal)
Wildfires (with Satellites) – ���Why and How?
Chris Waigl 2013-08-08, G&G Remote Sensing lunch seminar UAF
Chris Waigl,– [email protected] – Remote sensing of (boreal) wildfires (with satellites): Why and how? – 2013-08-08 2
What’s special about Alaska (and the whole boreal zone)?
Image: Alaska Climate Research Center
Chris Waigl,– [email protected] – Remote sensing of (boreal) wildfires (with satellites): Why and how? – 2013-08-08 3
Why? Global (or regional) fire maps
NASA MODIS Global Firemap - July 10-19, 2013
Chris Waigl,– [email protected] – Remote sensing of (boreal) wildfires (with satellites): Why and how? – 2013-08-08 4
How is it spreading? Where does the smoke go?
Steward Creek 2 fire 2013- Alaska Fire Service
Chris Waigl,– [email protected] – Remote sensing of (boreal) wildfires (with satellites): Why and how? – 2013-08-08 5
How severe is it? How is it impacting the ecosystem? à Ecology
Steward Creek 2 fire 2013- Image Alaska State Parks
Chris Waigl,– [email protected] – Remote sensing of (boreal) wildfires (with satellites): Why and how? – 2013-08-08 6
How? Passive remote sensing from polar-orbiting satellites
For example, MODIS
! 36 bands: 20 reflective visible and short-wave infrared (250-500m resolution), 16 emissive mid and thermal IR1000m
! Up to 8 “good” images of Alaska / day
Trade-off between resolution in time and space: http://www.youtube.com/watch?v=V0hsCD4qZMk
Chris Waigl,– [email protected] – Remote sensing of (boreal) wildfires (with satellites): Why and how? – 2013-08-08 7
We measure the intensity of radiation emitted by the fire
Chris Waigl,– [email protected] – Remote sensing of (boreal) wildfires (with satellites): Why and how? – 2013-08-08 8
Landsat (July 7, 2009)
Chris Waigl,– [email protected] – Remote sensing of (boreal) wildfires (with satellites): Why and how? – 2013-08-08 9
Zooming in…
Chris Waigl,– [email protected] – Remote sensing of (boreal) wildfires (with satellites): Why and how? – 2013-08-08 10
Time series: July 4-7, 2009, MODIS over Landsat
Chris Waigl,– [email protected] – Remote sensing of (boreal) wildfires (with satellites): Why and how? – 2013-08-08 11
2004 Boundary Fire – MODIS Terra
What’s in a pixel? • shape • overlap • distortion
1 px = 1 x 1 km
at nadir (= looking straight down)
Chris Waigl,– [email protected] – Remote sensing of (boreal) wildfires (with satellites): Why and how? – 2013-08-08
2004 Boundary Fire – simultaneous ASTER image
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1 px = 30 x 30 m
Chris Waigl,– [email protected] – Remote sensing of (boreal) wildfires (with satellites): Why and how? – 2013-08-08
2004 Boundary Fire – sub-pixel fire temperature���= temperature of the portion of the pixel that is actually on fire
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Chris Waigl,– [email protected] – Remote sensing of (boreal) wildfires (with satellites): Why and how? – 2013-08-08
Different method: Active remote sensing with microwaves (radar backscatter - SAR)
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new burn
old fire scar
Chris Waigl,– [email protected] – Remote sensing of (boreal) wildfires (with satellites): Why and how? – 2013-08-08
Overlaying MODIS hotspot pixels on SAR
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Chris Waigl,– [email protected] – Remote sensing of (boreal) wildfires (with satellites): Why and how? – 2013-08-08
Different method: Thermal aerial imagery
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Chris Waigl,– [email protected] – Remote sensing of (boreal) wildfires (with satellites): Why and how? – 2013-08-08
Thanks!
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Lime River fire 2013- Alaska Fire Service
Data and imagery courtesy of: • Alaska Fire Service/AICC • U.S. Geological Survey • NASA’s Earth-Sun System Division • Martin Stuefer
• Alaska Climate Research Center • Alaska Satellite Facility/SAR Data Center • Alaska State Parks