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Register for Webinar on GPM Ground Validation Campaign OLYMPEX: 20 October

The Olympic Mountain Experiment (OLYMPEX) is a NASA-led field campaign that will take place on the Olympic Peninsula of Washington State from November 2015 through February 2016. The goal of the campaign is to collect detailed atmospheric measurements that will be used to evaluate how well rain-observing satellites measure rainfall and snowfall from space. In particular, OLYMPEX will be assessing satellite measurements made by the Global Precipitation Measurement (GPM) mission Core Observatory, a joint mission by NASA and the Japan Aerospace Exploration Agency (JAXA), which launched in 2014.

On 20 October (3:30 PDT/6:30 EDT), a special webinar will be held for educators covering the field campaign. During the webinar, Dr. Lynn McMurdie of the University of Washington, Project Manager and Senior Research Scientist for OLYMPEX, will discuss the specific scientific purposes of the project and why the Olympic Peninsula is a particularly significant locale for studying rain and snow, as well as detail the tools and equipment used for measurements during the campaign. In addition, Kristen Weaver, an Education Specialist for the GPM mission, will outline educational resources available to help your students learn about the campaign and the scientific work being done. (For more information on this campaign, visit or To view the accompanying educational materials, visit

What is Ground Validation?

The GPM Core Observatory and other rain-observing satellites orbit Earth hundreds of miles above the ground. From that altitude, they have a clear view of clouds and storms over nearly 90 percent of Earth (the angle of the orbit means the GPM Core Observatory misses the poles). In order to ensure that the satellite measurements of rainfall and snowfall are accurate from space, scientists make measurements from ground-based stations as storms pass over, while aircraft aircraft fly overhead with instruments that simulate the satellites' instruments. This lets them accurately compare the best estimate of truth on the ground to the view of precipitation from above.

The Olympic Peninsula is an ideal location to conduct a ground validation field campaign. Situated in the northwest corner of Washington State, the peninsula is home of the only temperate rain forest in the Northern Hemisphere. Its active winter storm season consists of wet weather systems traveling from the Pacific Ocean, over the coastal region and into the Olympic Mountains. The peninsula reliably receives annual precipitation amounts ranging from over 100 inches (2500 mm) on the coast to about 180 inches (4500 mm) in the forested mountainous interior.

Teams of scientists have set up ground instruments including rain gauges, advanced weather radars, and balloon launching sites to monitor incoming storms. Simultaneously, they will collect data from three aircraft flying through and above rain clouds, as well as from the GPM Core Observatory and other rain-observing partner satellites when they pass overhead.

Scientists will then use the detailed data sets to improve their understanding of the processes in the atmosphere that cause precipitation and to improve the computer programs that interpret satellite measurements of rainfall and snowfall from space.

type: globe-news

News origin: GLOBE Implementation Office