NASA study checks global warming trends

A new study by NASA researchers has verified the accuracy of recent global warming figures.

The team used measurements of the "skin" temperature of the Earth taken by a satellite infrared measurement system called AIRS (atmospheric infrared sounder) from 2003 to 2017.

They compared them to surface air temperature anomaly analyzes performed by stations, mainly the Goddard Institute for Space Studies (GISTEMP).

They found a high level of consistency between the two datasets over the past 15 years. Their results are published today in Letters of research on the environment.

Dr. Joel Susskind, lead author of NASA's Goddard Space Flight Center, commented on the study: "The AIRS data complements the GISTEMP because their spatial resolution is superior to that of GISTEMP and their global coverage is more complete. .

"Both datasets demonstrate that the Earth's surface has warmed globally during this period, and that 2016, 2017 and 2015 have been the warmest years in the instrument registry. , in this order.

"This is important because of the keen interest in the details of how estimates of global and regional temperature variations are constructed from surface temperature data and how the known imperfections of the raw data heat island effects) are treated ".

AIRS data reflects the temperature of the skin on the surface of oceans, land and snow and ice covered areas. Surface data is a mixture of atmospheric surface anomalies of one meter on Earth and sea surface temperature anomalies in bulk in the ocean.

To compare the two, the researchers constructed one-time monthly climatologies on the grid for each calendar month and for each data set, averaging the monthly values ​​from 2003 to 2017, with anomalies for a given month, for a year. given, defined by the difference between the value of the grid point for this month from its monthly climatology.

Dr. Gavin Schmidt, co-author of NASA's Goddard Institute for Space Studies, said: "Interestingly, our results revealed that surface datasets may underestimate the changes in temperature in the Arctic.This means that warming occurs can occur faster than expected.

"Our work also shows that complementary satellite surface temperature analysis is an important validation of surface-based estimates and could provide a way forward for improving surface-based products that could potentially be extended. to several decades. "