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MODIS imagery of the snowstorm in Jan. 2022
The Investigation of Microphysics and Precipitation for Atlantic Coast-Threatening Storms ( IMPACTS ) mission, now in its second year, is flying aircraft into snowstorms in order to improve meteorological models and our ability to use satellite data to predict how much snow will fall and where. NASA and its partners have several satellites that measure precipitation from space, such as the Global Precipitation Measurement (GPM) mission that observes rain and snow around most of the world every three hours. “But satellites can’t tell us a lot about the particles – the actual snowflakes ­– and
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...
Finding Strong Storms with TRMM & GPM
Spring is severe storms season here in the US, but not everyone has NEXRAD radar coverage; however, NASA’s TRMM and GPM satellites with their onboard radars have made it possible to search the entire global Tropics and midlatitudes and systematically identify areas where there are strong to intense thunderstorms. Researchers now headed by Dr. Chuntao Liu at Texas A&M University have built a comprehensive database of “precipitation features” based on regions of contiguous radar echoes from first the TRMM and now the GPM satellite. These precipitation features can then be mined to locate areas...
TMPA Shows El Niño Conditions in the Pacific
An El Niño that began to form last fall has matured and is now fully entrenched across the Pacific. Changes in sea surface temperatures, or SSTs, brought about by an El Niño affect the atmosphere, resulting in distinctive changes in the rainfall pattern across the Pacific Basin. These changes show up as anomalies or deviations in NASA’s analysis of climatological rainfall. This map shows sea surface temperature (SST) anomalies for the Pacific Basin, shown as degrees Celsius above or below average. Credit: NOAA Climate Prediction Center. In a typical El Niño, warmer than average SSTs off of the...
Top 5 GPM Research Highlights
GPM celebrates its fifth anniversary since launching from Tanegashima Island, Japan on February 27, 2014. This milestone not only marks the launch but also the many scientific research accomplishments that GPM has made in advancing our understanding of precipitation, from light rain to intense thunderstorms, to further our understanding of the water cycle. Here are five of GPM’s most significant research accomplishments and their contributions to weather and climate science in its first five years in space: Snowfall and Cold Season Precipitation An image of GPM’s DPR concept of dual-frequency...
GPM Gets Flake-y
In this video GPM Project Scientist Dr. Gail Skofronick-Jackson explains how scientists can measure the size, shape and distribution of snow particles, layer by layer, in a storm using GPM. The Global Precipitation Measurement mission is an international satellite project that provides next-generation observations of rain and snow worldwide every three hours.

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