The Effects of Particulate Matter 2.5 µm and Ozone on Climate and Health

Under the NOAA Center for Atmospheric Sciences (NCAS) Project, a study has been undertaken to investigate the interactions between Particulate Matter (PM) 2.5 µm and Ozone during the June 24, 2009 dry Saharan Air Layer (SAL) out break. This study measured PM 2.5 by using MODIS optical depth during the June 24, 2009 SAL event and observed that the particulate matter levels were elevated. Ozone levels were found using NASA's Total Ozone Mapping System (TOMS) for the aforementioned event. Also, the effects of the SAL on Sea Surface Temperature (SST) over the Atlantic were examined and the results showed a cooling effect. The possible health effects of PM 2.5 µm in SAL and non-SAL environments, such as respiratory issues, as well as its effects on incoming long-wave radiation were analyzed. The iron rich PM 2.5 µm reflects sunlight, and leads to atmospheric cooling as well as enhanced condensation. However, there is lack of precipitation as the formed droplets are too small to fall and do not readily coalesce. These effects, the reflection of long-wave radiation and the formation of non-rain bearing clouds, may also have longer lasting climatic impacts.