A dust storm swept through the Tigris–Euphrates river basin in mid-December 2024. Blowing hundreds of kilometers from eastern Syria and northern Iraq toward the Persian Gulf, the plume degraded visibility and caused hazardous air quality in several cities, including Baghdad, home to nearly 8 million people.
The dense dust cloud obscured the landscape in this image acquired by the MODIS (Moderate Resolution Imaging Spectroradiometer) on NASA’s Aqua satellite on December 14. Notice how the dust has organized into linear bands. The pattern is likely due to atmospheric gravity waves, caused by the rise and fall of an air mass that has been disturbed, for example, by flowing over topography.
Dust choked the air in the Iraqi capital of Baghdad on December 14. The Associated Press published a video that day showing blowing sand and low visibility in the city. Levels of fine particulate matter (PM2.5) exceeded 400 micrograms per cubic meter, according to data reported by IQAir. The World Health Organization classifies concentrations above 250 micrograms per cubic meter as hazardous, putting the public at high risk of adverse health effects.
The plume traveled farther toward the Persian Gulf and shrouded the city of Abadan in Iran, southeast of this scene, on December 15. Air quality there also reached hazardous levels, schools and public services were closed, and flights were suspended as visibility dropped, according to media reports.
The Tigris–Euphrates river basin is the primary non-desert source of dust in the Middle East and a very active area for dust events. They are most common during the drier summer months, brought on by the shamal—strong winds that blow from the north-northwest. However, the shamal winds also blow in winter, albeit in shorter and less intense incidents, with gusts reaching up to 70 kilometers (43 miles) per hour.
Dry conditions make it more likely that winds can loft eroded material into the air and transport it downwind. In a 2023 study, researchers analyzed data from the GRACE (Gravity Recovery and Climate Experiment) satellites and found a declining trend in terrestrial water storage in the Tigris–Euphrates river basin throughout the mission’s duration, from 2002 to 2017. Combining those observations with models of land surface processes, they attributed about 60 percent of the trend to climate variability and about 40 percent to direct human actions such as groundwater pumping and surface water withdrawal.
NASA Earth Observatory image by Michala Garrison, using MODIS data from NASA EOSDIS LANCE and GIBS/Worldview. Story by Lindsey Doermann.
