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Average Precipitation Daytime vs. Nighttime
During the summer, the U.S. Great Plains routinely experiences nighttime thunderstorms unlike anywhere else in the country. These large-scale storms—sometimes spanning entire states—account for more than 40 percent of annual rainfall in some areas. They can bring much-needed rain to farms and help recharge aquifers, but extremely severe events can also destroy fields, homes, and lives. Scientists have been studying the region for decades to learn the underpinnings of this distinct, repetitive weather pattern.
Maps showing the Average Precipitation Rate in Lake Victoria, Africa - Day vs. Night
Lake Victoria is the largest lake in Africa and an economic and food security lifeline for roughly 30 million people living near its shores in Uganda, Kenya, and Tanzania. But it also takes lives. Cyclical, daily weather patterns around the lake create violent nighttime thunderstorms that kill roughly 3,000 to 5,000 fishermen per year. “This is definitely one of the stormiest places on Earth,” said Wim Thiery, a climate scientist at the Vrije Universiteit Brussel who has studied Lake Victoria for several years. “Almost every night, you see these intense thunderstorms and sometimes even water
IMERG Sees a Dry September
Rainfall was scarce across much of the country in the month of September, pushing the eastern and southern thirds of the country into drought conditions. IMERG, the Integrated Multi-satellitE Retrievals for GPM, is a unified satellite precipitation product produced by NASA to estimate surface precipitation over most of the globe.
Observing the Intertropical Convergence Zone with IMERG
The intertropical convergence zone or “ITCZ” roughly forms a band that circumnavigates the Earth near the Equator where the northeast trade winds in the Northern Hemisphere converge with the southeast trade winds in the Southern Hemisphere. Sailors have often referred to it as the “doldrums” due to its generally light winds. Yet, the ITCZ is an important part of the global circulation as it forms the ascending branch of the Hadley circulation. This is ultimately driven by incoming solar radiation, which peaks near the Equator. This warms the air and the ocean, causing warm buoyant air to rise...
How TRMM and GPM Study Latent Heating
Latent heating (LH) arises predominantly from the release of heat associated with the condensation of water vapor into cloud droplets in clouds with active updrafts. Other sources of LH include ice deposition and freezing, while evaporation, melting and sublimation induce cooling, but condensation is the dominant heating term. Like a hot-air balloon, LH can keep air parcels warmer than their surrounding environment and therefore rising. On a large scale, LH is responsible for driving the ascending branch of the Hadley Circulation. LH is also an important component in the dynamics of a regional...

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