Exploring Climate Change From Earth Orbit

glacier national park shows climate change effects
Glacier National Park, in Montana’s portion of the Rocky Mountains, is expected to be virtually glacier-free by around 2030. The blue areas in each of these false-color images are permanent snow and ice glaciers. The roughly 150 glaciers it contained in 1850 dwindled to 83 by 1968 and to 25 in 2015. (The white areas are clouds.) Glaciers in the Blackfoot-Jackson basin decreased from 21.6 square kilometers (8.3 square miles) in area in 1850 to just 7.4 square kilometers (2.9 square miles) in 1979. The 2015 image also shows burn scars from wildfires. These images were taken by the Thematic Mapper onboard Landsat 5 and the Operational Land Imager onboard Landsat 8. NASA Earth Observatory

Every minute of every day, eyes in the sky lofted into orbit by the world's space agencies study our planet and its atmosphere. They provide a constant stream of data on everything from air and ground temperatures to moisture content, cloud systems, pollution effects, fires, ice and snow cover, the extent of the polar ice caps, changes in vegetation, ocean changes and even the extent of oil and gas spills on both land and sea.

Their combined data gets used in many ways. We're all familiar with the daily weather reports, which are based in part on satellite imagery and data. Who among us hasn't checked the weather before heading out to work at the office or the farm? That's a very good example of the kind of "news you can use" from such satellites.

Weather Satellites: Tools of Science

There are many ways these orbiting Earth observatories help humans. If you're a farmer, you've likely used some of that data to help time your planting and harvesting. Transportation companies rely on weather data to route their vehicles (planes, trains, trucks, and barges). Shipping companies, cruise liners, and military vessels are incredibly dependent on weather satellite data for their safe operations. Most people on Earth rely on weather and environmental satellites for their safety, security, and livelihoods. Everything from daily weather to long-term climate trends are the bread and butter of these orbital monitors. These days, they're an important tool in tracking the effects of climate change that scientists have been predicting as levels of carbon dioxide (CO2) gas rise in our atmosphere. Increasingly, satellite data is giving everybody a head's-up on long-term trends in the climate, and where to expect the worst effects (floods, blizzards, longer tornado seasons, stronger hurricanes, and likely drought areas).

Seeing the Effects of Climate Change from Orbit

As our planet's climate changes in response to ever-greater amounts of carbon dioxide and other greenhouse gases being pumped into the atmosphere (which is causing it to warm up), satellites are rapidly becoming the front-line witnesses to what's happening. They provide stark evidence of the effects climate change have on the planet. Images, like the one shown here of the gradual loss of glaciers in Glacier National Park in Montana and Canada are the most compelling data. They tell us at a glance what is happening in various places on Earth. NASA's Earth Observing System has many images of the planet that show evidence of the effects of climate change.

For example, deforestation is visible to satellites. They can chart the of the die-out of plant species, the spread of insects (such as the pine beetle populations devastating parts of western North America), the effects of pollution, the devastation of flooding and fires, and drought-ridden regions where those events do a lot of damage. It's often said that pictures tell a thousand words; in this case, the ability of weather and environmental satellites to provide such detailed visuals is an important part of the toolbox scientists use to tell the story of climate change as its happening.

In addition to the imagery, satellites use infrared instruments to take the planet's temperature. They can take "thermal" images to show which parts of the planet are warmer than others, including the rise in sea ocean temperatures. Global warming appears to be changing our winters, and this can be seen from space in the form of reduced snow cover and thinning sea ice.

Recent satellites have been equipped with instruments that allow them to measure global ammonia hotspots, for example, Others, such as the Atmospheric Infrared Sounder (AIRS) and Orbiting Carbon Observatory (OCO-2) are focused direction on measuring the amount of carbon dioxide in our atmosphere.

Implications of Studying our Planet

NASA, as one example, has a number of weathersats that study our planet, in addition to the orbiters it (and other countries) maintain at Mars, Venus, Jupiter, and Saturn. Studying planets is part of the agency's mission, as it is for the European Space Agency, the China National Space Administration, Japan's National Aerospace Exploration Agency, Roscosmos in Russia, and other agencies. Most countries have oceanic and atmospheric institutions — in the U.S., the National Atmospheric and Oceanic Administration works closely with NASA to supply real-time and long-term data about the oceans and atmosphere. NOAA's clients include many sectors of the economy, plus the military, which depends heavily on that agency as it works to protect American shores and skies. So, in a sense, weather and environmental satellites around the world not only help people in the commercial and personal sectors, but they, the data they provide, and the scientists to analyze and report the data, are front-line tools in the national security of many countries, including the U.S.

Studying and Understanding Earth is Part of Planetary Science

Planetary science is an important area of study and is part of our exploration of the solar system. It reports on a world's surface and atmosphere (and in the case of Earth, on its oceans). Studying Earth is no different in some ways from studying other worlds. Scientists focus on Earth to understand its systems just as they study Mars or Venus to understand what those two worlds are like. Of course, ground-based studies are important, but the view from orbit is priceless. It gives the "big picture" that everyone will need as we navigate the changing circumstances on Earth.