Showing papers by "Warner L. Ecklund published in 1991"
TL;DR: Comparison of the results at Christmas Island during El Ni �o and non-El Ni�o conditions with earlier results obtained for stratiform rain conditions over Pohnpei, Federated States of Micronesia, show that cirrus clouds in the vicinity of the tropopause likely play an important role in determining the sense and magnitude of vertical motions in this region.
Abstract: Measurement from Christmas Island (2°N, 157°W) of long-term mean vertical motions in the tropical atmosphere using very-high-frequency wind-profiling Doppler radar show that there is a transition from downward motion in the free troposphere to upward motion in the upper troposphere and lower stratosphere. The observations in the free troposphere are consistent with a balance between adiabatic and diabatic heating and cooling rates in a clear atmosphere. Comparison of the results at Christmas Island during El Nino and non-El Nino conditions with earlier results obtained for stratiform rain conditions over Pohnpei, Federated States of Micronesia, show that cirrus clouds in the vicinity of the tropopause likely play an important role in determining the sense and magnitude of vertical motions in this region. These results have implications for the exchange of mass between the troposphere and stratosphere over the tropics.
72 citations
TL;DR: In this paper, the application of wind profiler Doppler radar technology to tropical atmospheric research is discussed, with the focus on the use of the wind profilers in the tropics.
Abstract: This paper is concerned with the application of wind-profiling Doppler radar technology to tropical atmospheric research. Examples of the use of wind profilers in the tropics are drawn from the Aeronomy Laboratory's wind profilers located on Pohnpei, Micronesia (7°N, 158°E), and Christmas Island (2°N, 157°W). The Pohnpei wind profiler was constructed in 1984 and has been used exclusively to observe vertical motions. The Christmas Island wind profiler has observed horizontal and vertical velocities routinely since 1986. These two wind profilers form part of a planned trans-Pacific network of wind-profiling radars that will eventually span the tropical Pacific.
59 citations
TL;DR: In this article, a set of examples to demonstrate the potential of VHF radar wind profilers for studying tropical convection processes is provided, extracted from data obtained from the NOAA/CU Pacific Profiler Network, which has been in operation for a number of years.
Abstract: In this paper we provide a set of examples to demonstrate the potential of VHF radar wind profilers for studying tropical convection processes. Our examples were extracted from data obtained from the NOAA/CU Pacific Profiler Network, which has been in operation for a number of years and is currently being expanded.
12 citations