On Friday (September 27, 2013), the Intergovernmental Panel on Climate Change (IPCC) released a landmark study showing unequivocal evidence that Earth’s climate system is warming. To accompany the data in the IPCC report, the U.S. National Aeronautics and Space Administration (NASA) has produced a new video that shows what changes in temperature and precipitation can be expected for the 21st century if CO2 concentrations in the atmosphere continue to rise from the current level of approximately 400 parts per million (ppm) to an anticipated 670 ppm by 2100. The video illustrates what a warmer world will look like and identifies what regions will likely experience the most warming. In general, warming is expected to be more pronounced over land than in the ocean and the largest increases in temperature are expected to occur across the Northern Hemisphere.
According to the video:
All around the globe, the land areas show a greater increase in temperature than the surrounding ocean waters. Evaporation of the water helps to keep the ocean surface cool and the deep depths of the ocean have a large capacity to absorb energy before heating up.
The largest changes in temperatures are expected to occur in the Northern Hemisphere, and areas such as the Rocky Mountains and northern Canada could experience some of the earliest effects of the warming trend. As snow in the Arctic region melts, less sunlight will be reflected off the surface of the Earth and warming there will be accentuated.
Precipitation is expected to increase in some regions of the world and decrease in others. In general, dry regions could become even drier and wet regions could become even wetter.
The data presented in the NASA video were projected using the same climate models that were featured in the IPCC 5th assessment report. However, the baseline for analysis used in NASA’s visual representation ranged from 1971 to 2000, whereas the baseline for analysis in the IPCC report ranged from 1986 to 2005. Hence, the climate data projections for the two projects are slightly different even though the trends depicted are largely the same.
Bottom line: To accompany the IPCC report released on September 27, 2013, NASA has produced a new video that shows what changes in temperature and precipitation can be expected if atmospheric CO2 concentrations continue to rise. In general, warming is expected to be more pronounced over land than in the ocean and the largest increases in temperature are expected to occur in the Northern Hemisphere.