Restoring a healthy balance between sea otters and their sea urchin prey comes with a modest but meaningful bonus: halting the overgrazing of kelp forests and increasing their ability to remove excess carbon dioxide from the atmosphere.
Humans currently release about 70 million tons of carbon dioxide every day into the atmosphere and about 20 million tons is being absorbed regularly by the oceans, causing the pH to drop. Chris Sabine describes current and projected future impacts of this acidification on marine ecology.
Each of the last three decades was warmer than all earlier decades in the instrumental record, and each set a new and statistically significant record, culminating in the 2000s, which was the warmest decade of all.
Global climate models project that near the end of the 21st century, average surface temperature over most of Earth’s surface will be several degrees warmer than today, mainly due to rising levels of greenhouse gases in the atmosphere.
Students explore the carbon cycle and the relationship between atmospheric carbon dioxide concentrations and temperature. Students create and compare graphs of carbon dioxide and temperature data from one local (Mauna Loa, Hawaii) meteorological station and one NASA global data set. These graphs, as well as a global vegetation map and an atmospheric wind circulation patterns diagram, are used as evidence to support the scientific claims they develop through their analysis and interpretation.