Monitoring and measuring change using satellites
There are a variety of ways that scientists measure and monitor change over time across the Earth's surface. Geographers often use geospatial data and tools to do this, including Global Positioning System (GPS) data, Geographic Information Systems (GIS) and remote sensing. Space-borne satellites that are in geosynchronous orbit around the Earth (meaning that the time it takes to orbit Earth is equal to one Earth day) have been "looking back" at the surface of the Earth and collecting remotely sensed data for over four decades now, allowing scientists to measure some amazing changes on the surface and try to understand why they are happening. Additionally, these types of satellites provide an incredible amount of day-to-day information about the weather (including the data that weather forecasters use), the amount of snow on the ground, the amount of water in rivers and lakes, and numerous natural hazards, including hurricanes, tornadoes, wildfires, floods, and drought.
One example of how remotely sensed data from a satellite gets used is the MODIS fire product. MODIS is an acronym that stands for Moderate-resolution Infrared Spectroradiometer; this means that the satellite "sees" light across both the visible (which we humans can see) and the infrared (which we can't see with the naked eye) part of the electromagnetic spectrum. The MODIS sensor acquires data over the entire Earth surface every single day. One of the phenomena it can "see" is wildfires burning on the Earth surface. Before MODIS was launched into orbit in 2000, wildfires had to be found and reported by fire tower lookouts, airline pilots, and citizens who saw smoke columns. Now, MODIS is used to find new fires every single day, which ensures that fire managers can find and deal with fires in somewhat remote areas much more quickly and efficiently.
On the online resource for your textbook, there is a video on how MODIS is used to monitor and measure wildfires around the globe. Log in to BBLearn, go to Module 1, and click on the Study Area. Click on 'Videos,' then click on the video listed for Chapter 2: "Studying Fires Using Multiple Satellite Sensors." This will open as a pop-up (so your computer must allow pop-up windows). Watch the video and answer the questions below.
1. The global data show distinct fire 'seasons' when fires are active in different regions. Africa has two distinct fire seasons: one in Southern Africa and the second in Northern Africa. What is the seasonal timing of these two fire seasons -- in what months are most of the fires burning in each region?
2. The video mentions that data from multiple satellite sensors can be used to look at the relationships between environmental factors and fire. What are two examples of environmental factors associated with fire shown in the video?
3. How are landcover data used in conjunction with the fire product maps?
4. What kind of landcover was burned by the Hayman Fire in Colorado in 2002?
5. What kind of sensor data (i.e., what range of the electromagnetic spectrum) allows scientists to identify burned areas on the Biscuit Fire by their purple color?
One example of how remotely sensed data from a satellite gets used is the MODIS fire product. MODIS is an acronym that stands for Moderate-resolution Infrared Spectroradiometer; this means that the satellite "sees" light across both the visible (which we humans can see) and the infrared (which we can't see with the naked eye) part of the electromagnetic spectrum. The MODIS sensor acquires data over the entire Earth surface every single day. One of the phenomena it can "see" is wildfires burning on the Earth surface. Before MODIS was launched into orbit in 2000, wildfires had to be found and reported by fire tower lookouts, airline pilots, and citizens who saw smoke columns. Now, MODIS is used to find new fires every single day, which ensures that fire managers can find and deal with fires in somewhat remote areas much more quickly and efficiently.
On the online resource for your textbook, there is a video on how MODIS is used to monitor and measure wildfires around the globe. Log in to BBLearn, go to Module 1, and click on the Study Area. Click on 'Videos,' then click on the video listed for Chapter 2: "Studying Fires Using Multiple Satellite Sensors." This will open as a pop-up (so your computer must allow pop-up windows). Watch the video and answer the questions below.
1. The global data show distinct fire 'seasons' when fires are active in different regions. Africa has two distinct fire seasons: one in Southern Africa and the second in Northern Africa. What is the seasonal timing of these two fire seasons -- in what months are most of the fires burning in each region?
2. The video mentions that data from multiple satellite sensors can be used to look at the relationships between environmental factors and fire. What are two examples of environmental factors associated with fire shown in the video?
3. How are landcover data used in conjunction with the fire product maps?
4. What kind of landcover was burned by the Hayman Fire in Colorado in 2002?
5. What kind of sensor data (i.e., what range of the electromagnetic spectrum) allows scientists to identify burned areas on the Biscuit Fire by their purple color?