SAHARA GREENING STRENGTHENS TROPICAL CYCLONE ACTIVITY

Tropical cyclones can cause devastations, including loss of human lives and expensive damages. Researchers from the Department of Meteorology at Stockholm University (MISU) have created a series of model simulations to analyze tropical cyclone activity- the mid-Holocene which occurred during a warm climate some 6,000 years before.

Today’s hyper-arid Sahara desert then had lush grass coverage which reduced dust emission owing to Earth's orbital parameters changes. These orbital forcing changes caused more powerful summer insulation (sun-ray’s exposure) in the Northern Hemisphere, resulting in stronger monsoons worldwide.
Past researches on the response of tropical cyclones to past climates have only investigated the impact of solar radiation changes from orbital forcing on the generation of tropical cyclones. The reactions to the greening of the Sahara were not considered.

The current research which included Saharan vegetation changes and dust emissions found that the greening of Sahara would intensify the West African monsoon, which induces a change in the atmospheric circulation over the whole of tropics, influencing tropical cyclone activity.
This research concludes that climate models should therefore also represent changes in land cover for projecting future climate. This research has been published in PNAS- a scientific journal.

Content: www.sciencedaily.com