Visualizing global temperature trends

In January 2014, NASA released a report on 2013 global surface temperatures revealing that "the average  temperature in 2013 was 58.3 degrees Fahrenheit (14.6 degrees Celsius), which is 1.1 °F (0.6 °C) warmer than the mid-20th century baseline" and tied with 2006 and 2009 for the seventh warmest year since 1880. Accompanying graphics and an animation of  global temperatures from 1950 through the end of 2013 are also available along with a written summary of the results (pdf) by Dr. James Hansen. This summary also contains graphics and visualizations that can be useful in the classroom. Furthermore, you can generate a surface temperature anomaly or trend map using the following tool and the resulting map can be downloaded as a pdf - the map below is one I created showing December 2013 temperature anomalies relative to 1951-1980 base period. The visualization reveals that this month brought exceptionally cooler temperatures in North America and warmer than average temperatures to northeast Europe and Siberia.

Another tool that might be useful when discussing temperature trends up through 2012 is a new Google Earth/Google Maps tool that shows how land surface temperature has changed since as far back as 1850 for some regions. The University of East Anglia's Climatic Research Unit divided Earth's land surfaces into equally sized grid cells and calculated the average annual temperature for each cell using temperature data acquired from monitoring equipment. You'll notice that the cells appear either red or green but these colors are not indicative of a particular trend. In order to view the annual (and seasonal) surface temperature trend (an corresponding data) for a particular cell, simply click on that cell and a graphic will appear that shows the temperature anomaly from the 1961-1990 mean. Below is the graphic for the cell that includes the area of North Carolina in which I live. To learn more about this tool click here. You could use this tool with students to examine seasonal trends for a region, to examine different regions of the globe and to emphasize that there are places on the globe where there is not adequate data for trend analysis due to short temperature records and/or lack of monitoring stations.

Educators Guide to NASA Earth Science Images and Data

The Educators Guide to NASA Earth Science Images and Data is a free booklet (available in pdf) designed with teachers in mind. The guide organizes NASA Earth science data and imagery into three sections: Introductory, Intermediate and Advanced and you can also use the guide to find relevant imagery and data from specific NASA missions. In addition, there are Educator’s Tool Belt sections found throughout the booklet that offer examples of how teachers have incorporated certain resources into their science instruction.

NASA Interactive Poster

This interactive visualization from NASA features images from over a dozen Earth observation missions, providing 25 unique views of Earth's atmosphere, biosphere, land surface, solid Earth, and ocean. Clicking on a tile will take you to a visualization of a data set from a particular mission. The image below shows a visualization of land surface temperature acquired from data collected by the Aqua satellite. Additional tabs reveal details about the mission and links to additional resources.

The artwork on the main page was  developed for the NASA Earth Science Week 2013 Mapping Our World poster which is available for download (pdf). Additional resources to accompany this interactive visualization are available from the Educational Resources section. 

Fires and Floods

Given that my background is not in Earth science, I was intrigued when I learned about scientists tromping through the still burning remnants of California's Rim Fire to get a sense of which areas would be most susceptible to erosion so that erosion prevention measures can be implemented before any significant rainfall events.  And then I wondered, could the extreme flooding in Colorado this week have been exacerbated by drought and impacts to the land from past forest fires, such as the Flagstaff Fire of 2012?

Federal Teams Headed to Rim Fire to Assess Damage
ABC News, Sept 6th, 2013

Amid Drought, Explaining Colorado’s Extreme Floods
National Geographic, Sept 14th, 2013
 
Fire and Rain: The One-Two Punch of Flooding After Blazes
National Geographic, Aug 31st, 2011


It turns out that NASA satellite imagery can guide scientists to those forested areas needing attention by aiding in the identification of severely burned areas where destroyed vegetation and exposed soil could be problematic during a heavy rainfall or flooding event.  A Burned Area Reflectance Classification (BARC) is a satellite-derived data layer of post-fire vegetation condition. The BARC has four classes: high, moderate, low, and unburned (see map below).  To learn more about how BARC data is generated, click here.

Burned Area Reflectance Classification (BARC) for the June 2013 Silver Fire

After a Fire, Before a Flood
NASA Earth Observatory, Sept 11, 2013

Burning Wildlands and a Burning Need for Landsat (pdf)

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/

Mapping the World’s Forests in Three Dimensions

Seeing Forests for the Trees and the Carbon:Mapping the World’s Forests in Three Dimensions is a resource from NASA's Earth Observatory that addresses the role of trees/forests in Earth's Carbon Budget and describes how scientists are using remote sensing to visualize the World's forests. Here you can find a map of the World's Forest Cover, World's Tree Canopy Height (providing a three dimensional view of global forests), and for the US, an map showing  Aboveground Woody Biomass (left).   A combination of text, images and maps, this student friendly resource would be an excellent item for students to explore via a WebQuest activity.

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.

Melting Permafrost and Methane

In a warming world, permafrost, which comprises 24% of the land in the Northern Hemisphere is at risk of melting, releasing its stored carbon in the form of carbon dioxide and methane.

Methane hydrates have been in the news lately after Japan announced in March that it had extracted natural gas from deep in the ocean floor!  The source of the natural gas was methane hydrates, or methane molecules trapped in ice crystals.  In reading a recent National Geographic article, I learned that “methane hydrates buried beneath the seafloor on continental shelves and under the Arctic permafrost are likely the world’s largest store of carbon-based fuel. The figure often cited, 700,000 trillion cubic feet of methane trapped in hydrates, is a staggering sum that would exceed the energy content of all oil, coal, and other natural gas reserves known on Earth.”

Below are some links for learning more about methane & permafrost:

Wunderground: Permafrost in a Warming World


NASA: Methane: A Scientific Journey from Obscurity to Climate Super-Stardom

NASA Mission: Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE)
 
Nature Education Knowledge: Methane Hydrates and Contemporary Climate Change

UNEP: Policy Implications of Warming Permafrost (See Chapter 4)

Using Landsat to Study Permafrost

Using NASA's Landsat satellites, scientists have been able to assess how Earth's surface has changed from 1972 to the present. One example of how Landsat was used to study a "landscape of thawing permafrost" that resulted in coastal erosion and lake evolution in Cape Halkett, Alaska from 1955-2005 is described here and in a two-page pdf with accompanying satellite image. Additional Landsat images of the region can be found here.

NASA's Global Ice Viewer

NASA's Global Ice Viewer enables viewers to see how climate change has affected glaciers, sea ice, and continental ice sheets by focusing on Greenland, the Arctic and Antarctica.

Visit Antarctica to learn about the continent's major ice shelves, ice flow and extent of sea ice which is actually increasing!

This is a good time to remind you that you will want to be sure to distinguish between the Antarctic Ice Sheet - glacial ice - which is losing volume and Antarctic sea ice - frozen seawater - which is expanding. Two recent NASA articles may be of interest:

NASA study examines Antarctic sea ice increases

Ice sheet loss at both poles increasing, study finds

A Tour of the Cryosphere: Antarctica

NASA's A Tour of the Cryosphere is an animation that provides an overview of Earth's frozen surfaces using satellite observations and details the impact that recent cryospheric changes are making on our planet.

The 5 minute animation begins in Antarctica, showing some unique features of the Antarctic landscape found nowhere else on earth. Ice shelves, ice streams, glaciers, and the formation of massive icebergs can be seen clearly in the flyover of the Landsat Image Mosaic of Antarctica.

Still images of Antarctica, along with images from the collapse of the Larsen iceshelf are also available for download.

Satellite View of Antarctica

The Landsat Image Mosaic of Antarctica (LIMA) is the first-ever true-color high-resolution satellite view of the Antarctic continent enabling everyone to see Antarctica as it appears in real life. The primary purpose of the LIMA website is to provide materials that will allow for both students and educators to explore the continent.  The Meet Antarctica page provides an introduction to the continent; fact sheets along with high resolution images are also available for download. 

The Antarctic Mysteries page contains seventeen images (many of which are also available for high resolution download) that depict a variety of Antarctic features, from crevasses to icebergs, and provides a description of each.

Teaching about uncertainity when it comes to climate change

Although scientists have gained significant insight into how the Earth's climate system works, the nature of scientific inquiry tells us that there will never be 100% confidence in future climate projections for a variety of reasons.  As you and your students assess the value of climate models at predicting future climate and related climate change impacts, it is helpful to let students know the factors contributing to uncertainty.  These uncertainties can be broken down into two main categories: climate forcings, such as solar irradiance, greenhouses gas emissions and aerosols, which are primary drivers in shifting the Earth's climate, and climate feedbacks, such as clouds, which are secondary drivers, changing in response to a forcing. 

For a more detailed summary about key forcings and feedbacks that complicate climate models and future climate projections, read the NASA article Unresolved questions about Earth's climate.

Alignment to NC Essential Standards  (grades 9-12)
EEn.1.1.3
EEn.1.1.4
EEn.2.3.1
EEn.2.6