NASA researchers used measurements of the ‘skin’ temperature of the Earth taken by a satellite-based infrared measurement system called AIRS (Atmospheric Infra-Red Sounder) from 2003 to 2017.
The data from AIRS, along with station-based analyses of surface air temperature anomalies from the Goddard Institute for Space Studies Surface Temperature Analysis (GISTEMP) were compared and showed a very high level of consistency over the past 15 years.
The results of the NASA study were published Wednesday, April 17, 2019, in the journal, Environmental Research Letters. If anything, the researchers found, the pace of climate change could be somewhat more severe than previously acknowledged.
“We may actually have been underestimating how much warmer [the Arctic’s] been getting,” said Dr. Gavin Schmidt, who directs NASA’s Goddard Institute for Space Studies, which keeps the temperature data, and who was a co-author of the new study, reported the Washington Post.
Lead author of the study, Dr. Joel Susskind, from NASA’s Goddard Space Flight Center, explained that the AIRS and GISTEMP data sets showed consistent warming over the 14 year period and that 2016, 2017, and 2015 were the warmest on record, in that order, according to Phys.org.
“This is important because of the intense interest in the detail of how estimates of global and regional temperature change are constructed from surface temperature data, and how known imperfections in the raw data (due to station moves, gaps, instrument and practice changes, urban heat island effects) are handled.”
What is AIRS data?
NASA’s Aqua satellite, which has been in orbit since 2002, carries an infrared device called Atmospheric Infrared Sounder (AIRS) that is able to independently measure temperatures at the surface of Earth or the “skin.”
By “skin,” we are talking about surface ocean temperatures, and the surface of the land and snow/ice covered regions. To compare land-based surface temperatures and ocean bulk surface temperatures, every month, data grids are created to combine the data, giving a running average.
AIRS is designed to collect climate data and turn it into 3-D maps of air and surface temperature, water vapor and cloud properties, helping improve researchers’ understanding of severe weather patterns and how they relate to global climate change. The Aqua satellite is in Earth Orbit at an altitude of 438 miles (705.3 kilometers) above Earth’s surface.
“Interestingly, our findings revealed that the surface-based data sets may be underestimating the temperature changes in the Arctic. This means the warming taking place at the poles may be happening more quickly than previously thought,” said Dr. Schmidt. “What you end up with is a really impressive correspondence between the trends that you’re seeing in this satellite product, which is totally independent of the surface temperatures, and the interpretations of the weather stations.”
Zeke Hausfather, a researcher at the University of California at Berkeley who works on another of the temperature data sets — called Berkeley Earth, commented on the study, although he was not involved. “These findings should help put to rest any lingering concerns that modern warming is somehow due to the location of sensors in urban heat islands or other measurement errors at the surface,” he said.
“The AIRS satellite data captures the whole surface of the planet and shows that, if anything, our surface measurements are slightly underestimating the rate of modern warming,” he added.
