Day 1: GCPEx Commences

Today the GPM Cold-weather Precipitation Experiment (GCPEx) officially began, and instead of snow, all that came down from the sky was cold rain.

Map of Ontaria where GCPEx takes place
Location of the GCPEx experiment

Fortunately Environment Canada's Weather Office says significant snow (and, yes, freezing rain, too) is on the horizon for Southern Ontario, where ground stations instrumented to within an inch of their lives are situated.

The main GCPEx ground station is at the Centre for Atmospheric Research Experiments (CARE) in Egbert, Ontario, about 44 miles (70 km) north of Toronto and about 27 miles (44 km) southeast of Lake Huron. Four other smaller sites are located from 5 to 32 miles (8 to 52 km) away to capture snow in different areas.

The experiment is set up in layers to observe the same batch of snow from its formation in the clouds -- measured by two planes flying through the clouds, as it falls -- measured from the clouds to the ground by radar and radiometers (more on how these work to come), and finally when it lands on the ground -- measured by a network of snow gauges and other instruments at CARE.

Map of the ground site layout for the GCPEx field campaign. Layout of the primary (CARE) ground site along with the secondary sites GCPEx East (SkyDive), GCPEx South (SteamShow Fairgrounds), GCPEx West (B. Morton), and Huronia airport. Distances between sites and CARE are indicated. Location of the King City Radar with azimuth and range to CARE site is also indicated.

NASA and Environment Canada are working together to gather as much data on snow as they can to improve scientists' knowledge base and then to use all that new data to help satellites make better measurements of snow from space.

We'll be following just how the scientists and engineers will do that in this blog with reports from the field and a closer look at the instruments that will measure snow in Canada, and eventually from low earth orbit.

Some links to check out as we get rolling: