Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Spatial and Temporal Extrapolation of Disdrometer Size Distributions
  Based on a Lagrangian Trajectory Model of Falling Rain   Methodologies to improve disdrometer processing, loosely based on
mathematical techniques common to the field of particle flow and fluid
mechanics, are examined and tested. The inclusion of advection and vertical
wind field estimates appears to produce significantly improved results in a
Lagrangian hydrometeor trajectory model, in spite of very strict assumptions of
noninteracting hydrometeors, constant vertical air velocity, and time
independent advection during a radar scan time interval. Wind field data can be
extracted from each radar elevation scan by plotting and analyzing reflectivity
contours over the disdrometer site and by collecting the radar radial velocity
data to obtain estimates of advection. Specific regions of disdrometer spectra
(drop size versus time) often exhibit strong gravitational sorting signatures,
from which estimates of vertical velocity can be extracted. These independent
wind field estimates can be used as initial conditions to the Lagrangian
trajectory simulation of falling hydrometeors.

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The categories of this paper are: patt-sol
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The categories of this paper are: eess
9
The categories of this paper are: nlin
12
The categories of this paper are: nucl-th
5
The categories of this paper are: gr-qc
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The categories of this paper are: dg-ga
1
The categories of this paper are: cs
23
The categories of this paper are: solv-int
11
The categories of this paper are: hep-lat
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The categories of this paper are: q-alg
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The categories of this paper are: bayes-an
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The categories of this paper are: funct-an
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The categories of this paper are: ao-sci
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The categories of this paper are: hep-ex
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The categories of this paper are: acc-phys
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The categories of this paper are: stat