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Scientists have scanned our planet to take its ‘skin’ temperature and have confirmed that recent global warming measurements are accurate.
NASA has added even more scientific evidence that climate change is having significant negative effects on our planet. Using a satellite-based infrared measurement system called the atmospheric infrared sounder (AIRS), the US space agency collected its measurements of the ‘skin’ temperature of the Earth between 2003 and 2017.
Then, it compared these with station-based analyses of surface air temperature anomalies, mostly from the Goddard Institute for Space Studies Surface Temperature Analysis (GISTEMP). Now, in a paper published to Environmental Research Letters, NASA’s researchers have reported a high level of consistency between the two enormous datasets over the course of the 15-year period.
Dr Joel Susskind from NASA’s Goddard Space Flight Center said that AIRS data complements GISTEMP because it is at a higher spatial resolution than GISTEMP, and has more complete global coverage.
“Both datasets demonstrate the Earth’s surface has been warming globally over this period, and that 2016, 2017 and 2015 have been the warmest years in the instrumental record, in that order.
“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.”
Worrying Arctic discovery
AIRS data reflects skin temperature at the surface of the ocean, land and snow/icy regions. Meanwhile, surface-based data combines two-metre surface air data anomalies over land and bulk sea surface temperature anomalies in the ocean.
To draw a comparison between the two, the NASA researchers constructed monthly grid point climatologies for each month and for each dataset by averaging these monthly values over the 15-year period. Anomalies for each month in a given year were defined as the difference of the grid point value for that month from its monthly climatology.
Co-author of the study, Dr Gavin Schmidt, said of the research: “Interestingly, our findings revealed that the surface-based datasets 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.
“Our work also shows that complementary satellite-based surface temperature analyses serve as an important validation of surface-based estimates. They may point the way to make improvements in surface-based products that can perhaps be extended back many decades.”
