Search Results

You are looking at 1 - 3 of 3 items for :

  • Author or Editor: S. H. Melfi x
  • Bulletin of the American Meteorological Society x
  • Refine by Access: All Content x
Clear All Modify Search
S. H. Melfi
and
D. Whiteman

Observations of the water-vapor mixing ratio in the lower atmosphere and its temporal evolution have been made with a Raman lidar. Comparison with an independent radiosonde measurement indicated excellent agreement. The moisture structure, observed up to an altitude of 5 km and over an 80-min period during the early morning of 30 April 1985 (the present lidar is limited to night operation), showed temporal variations of several atmospheric features which could not be resolved by balloon soundings. Application of the lidar should provide the opportunity to study details of atmospheric moisture, its structure, and its evolution in a manner never before realized.

Full access
J. E. M. Goldsmith
,
Scott E. Bisson
,
Richard A. Ferrare
,
Keith D. Evans
,
David N. Whiteman
, and
S. H. Melfi

Raman lidar is a leading candidate for providing the detailed space- and time-resolved measurements of water vapor needed by a variety of atmospheric studies. Simultaneous measurements of atmospheric water vapor are described using two collocated Raman lidar systems. These lidar systems, developed at the NASA/Goddard Space Flight Center and Sandia National Laboratories, acquired approximately 12 hours of simultaneous water vapor data during three nights in November 1992 while the systems were collocated at the Goddard Space Flight Center. Although these lidar systems differ substantially in their design, measured water vapor profiles agreed within 0.15 g kg−1 between altitudes of 1 and 5 km. Comparisons with coincident radiosondes showed all instruments agreed within 0.2 g kg−1 in this same altitude range. Both lidars also clearly showed the advection of water vapor in the middle troposphere and the pronounced increase in water vapor in the nocturnal boundary layer that occurred during one night.

Full access
M. P. McCormick
,
D. M. Winker
,
E. V. Browell
,
J. A. Coakley
,
C. S. Gardner
,
R. M. Hoff
,
G. S. Kent
,
S. H. Melfi
,
R. T. Menzies
,
C. M. R. Piatt
,
D. A. Randall
, and
J. A. Reagan

The Lidar In-Space Technology Experiment (LITE) is being developed by NASA/Langley Research Center for a series of flights on the space shuttle beginning in 1994. Employing a three-wavelength Nd:YAG laser and a 1-m-diameter telescope, the system is a test-bed for the development of technology required for future operational spaceborne lidars. The system has been designed to observe clouds, tropospheric and stratospheric aerosols, characteristics of the planetary boundary layer, and stratospheric density and temperature perturbations with much greater resolution than is available from current orbiting sensors. In addition to providing unique datasets on these phenomena, the data obtained will be useful in improving retrieval algorithms currently in use. Observations of clouds and the planetary boundary layer will aid in the development of global climate model (GCM) parameterizations. This article briefly describes the LITE program and discusses the types of scientific investigations planned for the first flight.

Full access