GEOS-CF animations

Health Air Quality Index (HAQI) as modeled by the GEOS-CF model for the time period October 10-23, 2017. The HAQI comprises of surface concentrations of NO2, PM2.5, and O3, using the formulation by Stieb et al. (2008). Values range from 0 (white, good) to 10 (hazardous air quality conditions). The time frame captures extensive wild fires over California and Portugal, as well as tropical storm Ophelia (Oct 15/16) transporting highly polluted air masses to the British Island.

Modeled surface concentrations of particulate matter with diameter of less than 2.5 microns (PM2.5), expressed in units of microgram per m3, for Delhi, India between Oct 26 and Nov 10, 2017 (top panel). Model 1-day hindcast and five day-forecasts are performed once a day with the GEOS composition forecast model (GEOS-CF). These concentration time series are shown in the bottom panel. Modeled concentrations are shown in dark red (hindcast) to yellow (5-day forecast). Corresponding observations (from the OpenAQ database) are shown in black.

Modeled surface concentrations of nitrogen dioxide (NO2), expressed in units of parts per billion (ppbv), for Zurich, Switzerland between Oct 26 and Nov 10, 2017 (top panel). Model 1-day hindcast and five day-forecasts are performed once a day with the GEOS composition forecast model (GEOS-CF). These concentration time series are shown in the bottom panel. Modeled concentrations are shown in dark red (hindcast) to yellow (5-day forecast). Corresponding observations (from the OpenAQ database) are shown in black. The model successfully captures the buildup of NO2 during the night (ozone titration) and the suppressed emissions during the weekend (reduced traffic).