Aerosol and Clouds
Study of the formation of the “black cloud” and its dynamics over Cairo, Egypt, using MODIS and MISR sensors
Article first published online: 10 NOV 2010
Copyright 2010 by the American Geophysical Union.
Journal of Geophysical Research: Atmospheres (1984–2012)
Volume 115, Issue D21, 16 November 2010
How to Cite
2010), Study of the formation of the “black cloud” and its dynamics over Cairo, Egypt, using MODIS and MISR sensors, J. Geophys. Res., 115, D21206, doi:10.1029/2010JD014384., , , , and (
- Issue published online: 10 NOV 2010
- Article first published online: 10 NOV 2010
- Manuscript Accepted: 21 JUL 2010
- Manuscript Revised: 6 JUL 2010
- Manuscript Received: 21 APR 2010
- air pollution;
- biomass burning
 In the past decade, episodes of severe air pollution, known as the “black cloud,” have occurred in Cairo, Egypt, in the early autumn. In this study, data from the Moderate Resolution Imaging Spectrometer (MODIS) and the Multi-angle Imaging Spectroradiometer (MISR) are used with meteorological data and trajectory analyses to determine the cause of these events. MODIS fire counts put the source as the burning of agricultural waste after harvest season in the Nile delta region. Synchronous MISR data show that these fires create low altitude (<500 m) plumes of smoke and aerosols which flow over Cairo in a few hours, as confirmed by Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) forward trajectory analyses. Much of the burning occurs at night, when an inversion constrains the plumes to remain in the boundary layer (BL). Convection during the day raises the BL, dispersing these smoke particles until the next night.