Who hasn’t spent time on their back gazing up at floating clouds, run ahead of a kite on a string, taken a deep breath of fresh air after a spring rain shower, or peered through an airplane window at the passing geography of Earth far below? Mention the word ‘air’ to many, and depending on where they live and how they grew up, it may also conjure up images of smog or smokestacks. But what is air, and do air quality and global warming have anything in common?
The Earth’s atmosphere consists of a layer of gases surrounding the planet. The atmosphere nourishes all life on earth with essential gases needed for photosynthesis and respiration, and with water vapor that falls as rain and snow. It also protects life by absorbing harmful ultraviolet radiation from the sun, warms the Earth by retaining heat, and dampens daily temperature extremes. The air that is mixed freely in the atmosphere, which we breath and which plants use for photosynthesis, consists of roughly 78% nitrogen, 21% oxygen, 0.93% argon and 0.039% carbon dioxide. And the atmosphere not only provides oxygen for all humans, plants and animals, but it also cycles carbon and nitrogen and is part of the Earth’s water cycle.
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Advancing Science. Informing Solutions.
- WHRC is studying how the rapid change in climate in the Arctic is affecting the release of more greenhouse gases into the air from the region’s wetlands and permafrost soils, thus accelerating the rate of human-caused climate change.
- WHRC has led scientific assessments of nitrogen in air pollution, including industrial and transportation sources of nitrogen oxides and agricultural sources of the heat trapping gas, nitrous oxide.
- WHRC has also researched the chemical characteristics of soot found on remote glaciers in order to identify the sources of this air pollution. This dark-colored soot is causing the glaciers to melt more rapidly and may also be affecting food webs in the rivers and oceans receiving the glacial meltwater.