On the consistency of CERES longwave flux and AIRS temperature and humidity profiles

SummaryApart from its normal functions in aviation the applications of radar have been few. In the post-war period T.R.E., in conjunction with the Meteorological Office, have been making a study of possible uses of radar to the science of meteorology and the results of these investigations are described in this paper.In the experimental work radar has been used to: —(a)investigate precipitation,(b)detect clouds dangerous to flying,(c)measure cloud height, and(d)measure wind speed and direction.An account is given of how radar may be used to measure the density of the atmosphere at altitudes up to many tens of miles and of some problems still to be solved in the design of a radar sonde system for measuring pressure, temperature and humidity profiles.It is concluded that radar will become an established meteorological tool and some possible profitable future lines of research are indicated.

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Clustering a Global Field of Atmospheric Profiles by Mixture Decomposition of Copulas

Journal of Atmospheric and Oceanic Technology ◽

10.1175/jtech1795.1 ◽

2005 ◽

Vol 22 (10) ◽

pp. 1445-1459 ◽

Cited By ~ 15

Author(s):

Mathieu Vrac ◽

Alain Chédin ◽

Edwin Diday

Keyword(s):

A Priori ◽

Distribution Functions ◽

Cumulative Distribution ◽

Specific Humidity ◽

Vertical Profiles ◽

Copula Functions ◽

Mixture Density ◽

Temperature And Humidity ◽

Priori Information ◽

Humidity Profiles

Abstract This work focuses on the clustering of a large dataset of atmospheric vertical profiles of temperature and humidity in order to model a priori information for the problem of retrieving atmospheric variables from satellite observations. Here, each profile is described by cumulative distribution functions (cdfs) of temperature and specific humidity. The method presented here is based on an extension of the mixture density problem to this kind of data. This method allows dependencies between and among temperature and moisture to be taken into account, through copula functions, which are particular distribution functions, linking a (joint) multivariate distribution with its (marginal) univariate distributions. After a presentation of vertical profiles of temperature and humidity and the method used to transform them into cdfs, the clustering method is detailed and then applied to provide a partition into seven clusters based, first, on the temperature profiles only; second, on the humidity profiles only; and, third, on both the temperature and humidity profiles. The clusters are statistically described and explained in terms of airmass types, with reference to meteorological maps. To test the robustness and the relevance of the method for a larger number of clusters, a partition into 18 classes is established, where it is shown that even the smallest clusters are significant. Finally, comparisons with more classical efficient clustering or model-based methods are presented, and the advantages of the approach are discussed.

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The Influence of Natural Ventilation to the Thermal and Moisture Environment in a Passive Greenhouse

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.374-377.57 ◽

2011 ◽

Vol 374-377 ◽

pp. 57-61

Author(s):

Lin Hua Zhang ◽

Li Na Chang

Keyword(s):

Natural Ventilation ◽

High Reliability ◽

Flow Temperature ◽

Temperature And Humidity ◽

And Control ◽

Temporal Field ◽

Homogeneous Temperature ◽

Humidity Profiles ◽

Humidity Field ◽

Typical Soil

The temperature and humidity profiles in spatial and temporal field inside the greenhouse are coupled to outside climates. Took a typical soil-walled passive greenhouse located in Jinan, Shandong, China as an example, an unsteady tri-dimensional numerical simulation was applied to solve the temperature and humidity profiles under natural ventilation conditions inside the greenhouse, based on the CFD program. The measurement was carried out to validate the CFD model, the results showed that the special temperature and humidity gradient were obvious inside the greenhouse, a homogeneous temperature and humidity field was obtained at crop level. The simulation results agree well with test values about the temperature and humidity inside the greenhouse with fitting degree of 99.8% and 99.7%, respectively. With high reliability, the model can be used as the basis to predict and control the environment inside the greenhouse. Greenhouse with natural ventilation under different wind conditions was simulated on a typical sunny day to predict the distribution of air flow, temperature and humidity field. By analyzing, some useful conclusions which can provide certain basis about the influence of natural ventilation on the thermal and moisture environment are deduced.

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