2022/09/01 BAMS State of the Climate

The 32nd edition of the international peer-reviewed BAMS State of the Climate report has been released on 31st of August 2022. It includes a contribution from a team of scientists led by HYGEOS, aiming to highlight the notable aerosol events of the year 2021. This contribution uses the CAMS Reanalysis (CAMSRA), a global reanalysis of atmospheric composition that spans 2003 to 2022. The CAMS reanalysis is a great tool to assess long term aerosol trends, as measured by aerosol optical thickness (AOD) at 500nm, as shown in the plot below:

AOD trends
CAMS reanalysis linear trends of total AOD for 2003-2021 and 2012-2021.

In 2021, aerosol optical depth (AOD) anomalies in the CAMSRA dataset reflect the Siberian and the North American extreme wildfire season in the summer of 2021, and the intensity of India's agricultural burning season. The long span of the CAMS reanalysis allows for a quantification of the number of extreme AOD days, as defined by the number of days in 2021 in which the CAMSRA AOD was above the 99.9% percentile for each location. In 2021, the extreme AOD days correspond to the extreme fire events already mentioned, including transport to the Arctic.
Extreme AOD days
CAMS reanalysis: number of days with AOD above the 99.9% percentile in 2021.