Wind Profiling Radar Dismantled on San Cristóbal Island


May 10, 2007

Personnel dismantle wind-profiling radar on Isla San 
Cristóbal in the Galápagos. During the month of April, researcher Leslie Hartten of CIRES and the NOAA Earth System Research Laboratory's Physical Sciences Division met with Director Carlos Lugo of Instituto Nacional de Meteorología e Hidrología (INAMHI) in Quito, Equador. Dr. Hartten thanked Lugo and INAMHI for their assistance over the past 14 years with a wind-profiling radar that NOAA operated on Isla San Cristóbal in the Galápagos. (Photo: Dr. Leslie Hartten and helpers dismantle a wind-profiler in San Cristóbal.)

Dr. Hartten then spent a few days working with the observers at the INAMHI site on San Cristóbal, dismantling the profiler and associated equipment for shipment back to the U. S. She also spent time with the site meteorologist discussing INAMHI's observations. Hartten learned about historical data from the site and about ongoing observations. These include thrice daily SST measurements and daily radiosondes, as well as weekly ozonesonde launches for ESRL's Global Monitoring Division.

Background:
In 1994 the former Aeronomy Laboratory's Tropical Dynamics and Climate group deployed this 915MHz wind profiling radar at Puerto Baquerizo Moreno on San Cristóbal Island as part of the now defunct Trans-Pacific Profiler Network (TPPN). The TPPN was a network of wind-measuring instruments at tropical island sites that spanned the Pacific Ocean basin. It was developed to examine the response of the atmosphere to El Niño ocean warming, so that insight could be gained into the changes in U.S. weather that are strongly influenced by El Niño.

Significance:
The profiler at San Cristóbal provided high-resolution research quality data about the movement of the air above the East Pacific Cold Tongue for approximately 10 of the last 13 years. While the radar at San Cristóbal was in operation, an hourly less-processed version of the wind data was transmitted to the Global Telecommunications System (GTS) and assimilated into forecast models at centers around the world. Research based on this data have revealed dramatic shifts in the seasonal cycle during the 1997-98 El Niño event as well as a decoupling in the low-level flow during periods with SST less than 23°C. The data collected contributes to the scientific basis for a more "global" weather forecast, so that societal impacts of the major multi-year weather variations can be better anticipated.

Contact: Leslie Hartten