53 research outputs found
Tropical island rainfall : a study of the rainfall distribution of Trinidad, West Indies
Originally issued as Reference No. 60-33, series later renamed WHOI-The study is based upon the concept that climatology
cannot be divorced from the dynamics of weather. An attempt is
made to outline the meteorological framework of this region of
the tropics. The rainfall of Trinidad is then discussed within
this framework. The mean annual distribution of rainfall over
the island forms a basis for the discussion of monthly distributions.
Seasonal variation is pointed out and related to broad scale migrations
of the subtropical anticyclones and the equatorial trough.
The dual rainfall maximum occurring during the wet season is, in
turn, related to the synoptic scale patterns of this season.
Distribution is then examined with reference to the moist layer,
wind direction and speed. Diurnal distribution is treated in
detail and the mechanisms giving rise to the well-defined distribution
patterns are discussed. Finally some attention is paid to
shower amounts and distribution. In conclusion the rainfall of
the island is summarized by relating the seasonal variations to
the broadscale meteorological background and the actual distribution
to the local scale influences
Design of the primary and secondary Pre-TRMM and TRMM ground truth sites
Results generated over six months are covered in five manuscripts: (1) estimates of rain volume over the Peninsula of Florida during the summer season based upon the Manually Digitized Radar data; (2) the diurnal characteristics of rainfall over Florida and over the near shore waters; (3) convective rainfall as measured over the east coast of central Florida; (4) the spatial and temporal variability of rainfall over Florida; and (5) comparisons between the land based radar and an optical raingage onboard an anchored buoy 50 km offshore
Trace gas and aerosol transports into and out of the Amazon Basin
Research under Agreement NCC1-106 during the interim period Oct. 1, 1991 to May 31, 1992 has continued to use the data collected during all three ABLE missions. The work reported on in this interim period includes published papers that cover the topic of global interactions between the rain forest of the Amazon Basin and local regional processes interior to the Basin itself
Atmospheric surface and boundary layers of the Amazon Basin
Three phases of work were performed: design of and preparation for the Amazon Boundary Layer Experiment (ABLE 2-A); execution of the ABLE 2-A field program; and analysis of the ABLE 2-A data. Three areas of experiment design were dealt with: surface based meteorological measurements; aircraft missions; and project meteorological support. The primary goal was to obtain a good description of the structure of the atmosphere immediately above the rain forest canopy (top of canopy to a few thousand meters), to describe this region during the growing daytime phase of the boundary layer; and to examine the nighttime stratified state. A secondary objective was to examine the role that deep convective storms play in the vertical transport of heat, water vapor, and other trace gases. While significant progress was made, much of the analysis remains to be done
Design of the primary pre-TRMM and TRMM ground truth site
The primary objective of the Tropical Rain Measuring Mission (TRMM) were to: integrate the rain gage measurements with radar measurements of rainfall using the KSFC/Patrick digitized radar and associated rainfall network; delineate the major rain bearing systems over Florida using the Weather Service reported radar/rainfall distributions; combine the integrated measurements with the delineated rain bearing systems; use the results of the combined measurements and delineated rain bearing systems to represent patterns of rainfall which actually exist and contribute significantly to the rainfall to test sampling strategies and based on the results of these analyses decide upon the ground truth network; and complete the design begun in Phase 1 of a multi-scale (space and time) surface observing precipitation network centered upon KSFC. Work accomplished and in progress is discussed
Abundances and density structure of the inner circumstellar ring around SN 1987A
We present optical spectroscopic data of the inner circumstellar ring around
SN 1987A from the Anglo-Australian Telescope (AAT) and the Very Large Telescope
(VLT) between ~1400 and ~5000 days post-explosion. We also assembled the
available optical and near-infrared line fluxes from the literature between
~300 and ~2000 days. These line light curves were fitted with a photoionization
model to determine the density structure and the elemental abundances for the
inner ring. We found densities ranging from 1x10^3 to 3x10^4 atoms cm^-3 and a
total mass of the ionized gas of ~0.058 Msun within the inner ring. Abundances
inferred from the optical and near-infrared data were also complemented with
estimates of Lundqvist & Fransson (1996) based on ultraviolet lines. This way
we found an He/H-ratio (by number of atoms) of 0.17+-0.06 which is roughly 30%
lower than previously estimated and twice the solar and the Large Magellanic
Cloud (LMC) value. We found an N/O-ratio of 1.5+-0.7, and the total
(C+N+O)/(H+He) abundance about 1.6 times its LMC value or roughly 0.6 times the
most recent solar value. An iron abundance of 0.20+-0.11 times solar was found
which is within the range of the estimates for the LMC. We also present late
time (~5000 - 7500 days) line light curves of [O III], [Ne III], [Ne IV], [Ar
III], [Ar IV], and [Fe VII] from observations with the VLT. We compared these
with model fluxes and found that an additional 10^2 atoms cm^-3 component was
required to explain the data of the highest ionization lines. Such low density
gas is expected in the H II-region interior to the inner ring which likely
extends also to larger radii at higher latitudes (out of the ring plane). At
epochs later than ~5000 days our models underproduce the emission of most of
these lines as expected due to the contribution from the interaction of the
supernova ejecta with the ring.Comment: 17 pages, 8 figures, accepted for publication in Ap
Investigation of the first and second aerosol indirect effects using data from the May 2003 Intensive Operational Period at the Southern Great Plains
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95668/1/jgrd12974.pd
Understanding Animal Detection of Precursor Earthquake Sounds
We use recent research to provide an explanation of how animals might detect earthquakes before they occur. While the intrinsic value of such warnings is immense, we show that the complexity of the process may result in inconsistent responses of animals to the possible precursor signal. Using the results of our research, we describe a logical but complex sequence of geophysical events triggered by precursor earthquake crustal movements that ultimately result in a sound signal detectable by animals. The sound heard by animals occurs only when metal or other surfaces (glass) respond to vibrations produced by electric currents induced by distortions of the earth’s electric fields caused by the crustal movements. A combination of existing measurement systems combined with more careful monitoring of animal response could nevertheless be of value, particularly in remote locations
Lase Validation Experiment
This report discusses the work done in validation the Lidar Atmospheric Sensing Experiment (LASE) data. This data was analyzed and compared to data from the RS-80 radiosonde. After an error was found and corrected in the programs used to analyze the LASE data, the results were closer to the results expected. The interpretation of the LASE measurements was based on the use of the Goddard Cumulus Ensemble model. This work is further described in the report
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