Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Analysis of the application of the optical method to the measurements of
  the water vapor content in the atmosphere - Part 1: Basic concepts of the
  measurement technique   We retrieved the total content of the atmospheric water vapor (or Integrated
Water Vapor, IWV) from extensive sets of photometric data obtained since 1995
at Lindenberg Meteorological Observatory with star and sun photometers.
Different methods of determination of the empirical parameters that are
necessary for the retrieval are discussed. The instruments were independently
calibrated using laboratory measurements made at Pulkovo Observatory with the
VKM-100 multi-pass vacuum cell. The empirical parameters were also calculated
by the simulation of the atmospheric absorption by water vapor, using the
MODRAN-4 program package for different model atmospheres. The results are
compared to those presented in the literature, obtained with different
instruments and methods of the retrieval. The reliability of the empirical
parameters, used for the power approximation that links the water vapor content
with the observed absorption, is analyzed. Currently, the total (from
measurements, calibration, and calculations) errors yield the standard
uncertainty of about 10% in the total column water vapor. We discuss the
possibilities for improving the accuracy of calibration to ~1% as indispensable
condition in order to make it possible to use data obtained by optical
photometry as an independent reference for other methods (GPS, MW-radiometers,
lidar, etc).

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The categories of this paper are: cond-mat
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The categories of this paper are: nucl-th
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The categories of this paper are: mtrl-th
9
The categories of this paper are: nlin
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The categories of this paper are: adap-org
36
The categories of this paper are: cmp-lg
30
The categories of this paper are: q-alg
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The categories of this paper are: quant-ph
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The categories of this paper are: solv-int
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The categories of this paper are: bayes-an
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The categories of this paper are: dg-ga
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The categories of this paper are: hep-th
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The categories of this paper are: q-bio
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The categories of this paper are: gr-qc
34
The categories of this paper are: chem-ph
32
The categories of this paper are: atom-ph