Using satellites to monitor wildfires

An August 2013 article from NASA titled, NASA 'Fire Towers' in Space Watch for Wildfires on the Rise, details the efforts being made to study fires from space and to study how climate change is impacting wildfires. According to NASA, instruments on Terra and Aqua, two of NASA’s Earth-observing satellites, have scanned the surface of our planet for over a decade to study fire’s role in land cover change, ecosystem processes and the global carbon cycle, allowing researchers to map characteristics of the global distribution of fires in remarkable detail.  A two minute video titled The Future of Fires summarizes NASA’s findings, which include the release of several animations that are also featured in the article: Potential Evaporation in North America Through 2100, and More Than a Decade of Fires.

Locations of actively burning fires around the world, July 2013

A visualization created with data from MODIS instruments aboard Terra and Aqua shows the global distribution of fires (above) and the distribution of aerosols (aerosol optical depth, below) from Jan 2005 - July 2013. This visualization can also be viewed as an animation.

Average monthly aerosol amounts around the world, July 2013

You can view, download, and analyze data on active fires and aerosol optical depth from NASA Earth Observations (NEO): 

Active Fires (Data from 2000-August 2013) 

Aerosol Optical Depth (Data from 2005-August 2013)

 

A Satellite-Based Forest Disturbance Monitoring System

I recently learned about the ForWarn Tool, a satellite-based forest disturbance monitoring system for the contiguous United States. This tool represents the combined efforts of USDA, NASA, USGS, and DOE and generates new potential disturbance maps every 8 days, even throughout the winter. This is a very user friendly tool and perfect for classroom use! 



Using this tool you can observe things like: declining hemlock forests in Western NC, forest fires and impacts to greenness, vegetation recovery after a tornado, etc. Images can be downloaded and corresponding NDVI graphs are also available.

Here is one example of something the tool can be used for - leaf out in the spring.  It was a cool spring, right? Especially compared to spring 2012. Using ForWarn, I can actually see (below) that, in the NC mountains, leaf out is less than expected - most likely due to the cooler spring temperatures we had in April and May.  By comparing current greenness with the "normal" greenness that would be expected for healthy, undisturbed vegetation growing at this location during this time, ForWarn shows that in Western NC, the amount of greenness between April 15 and May 8th, 2013 is less than expected (as indicated by the red, orange, yellow colors).

To acquire this image, I selected the Theme: MODIS Cumulative NDVI Products from the top tool bar, then from the left tool bar I selected "Forest Disturbance Detection maps" and then I selected the current image under "Change from All Year Baseline" by clicking on the light bulb to make it yellow (turning layer on). To see the legend, export the image, or graph NDVI, scroll to the far right.
 

ForWarn Resources

 

ForWarn Website

http://forwarn.forestthreats.org

ForWarn Tool

http://forwarn.forestthreats.org/fcav/#

Users Guide

http://forwarn.forestthreats.org/sites/default/files/FCAV_Users_Guide.pdf

Webinar Trainings

http://forwarn.forestthreats.org/support/training

Slideshow

http://www.geobabble.org/~hnw/first/webinar1/

Vegetation changes in the Arctic

This image of the day from NASA shows how the Normalized Difference Vegetation Index (NDVI), an indicator of photosynthetic activity or the “greenness” of the landscape, has changed over the past three decades (1982-2011) in the far northern latitudes of the Arctic. Rising temperatures in the Arctic are impacting the region's vegetation as described in a March 2013 publication in Nature Climate Change.

Researchers have documented that vegetation seasonality is diminishing, which means that there is an increase in plant growth. While treeless tundra ecosystems of the circumpolar Arctic were once  dominated by grasses, tall shrubs and trees have started to grow in their place. Boreal forests are also responding to a warmer Arctic; these forests showed different responses depending on whether conditions were drier (decreased photosynthesis) or wetter (increased photosynthesis) than usual.

References and related readings are available here.

Information on how scientists use remote sensing to study vegetation from space can be found here.