Near-surface air temperature estimation method under cloud conditions

Abstract

The invention provides a satellite remote sensing data-based near-surface air temperature estimation method under cloud conditions. The method comprises the following steps: (1) acquiring historical data of a meteorological station in a research area; (2) preprocessing the historical data of the atmospheric precipitation, the relative humidity near the ground, the cloud top temperature, the cloudtop height and the cloud optical thickness to obtain a spatio-temporal matching data set; (3) taking the temperature of the instrument shelter as the output of a neural network, taking the data set asthe input of the neural network, and constructing the neural network; (4) obtaining a data set of an area to be subjected to air temperature estimation; (5) carrying out time and space interpolationby utilizing a cubic spline interpolation method according to the latitude, longitude and time information of the meteorological satellite to obtain a data set matched with the space-time of the meteorological satellite; And (6) inputting the data set matched with the space-time space of the meteorological satellite into the constructed neural network to estimate the near-surface air temperature under the cloud day condition. The method is simple and easy to implement and high in precision.

Description

technical field [0001] The invention relates to the technical field of atmospheric remote sensing, in particular to a method for estimating near-surface air temperature under cloudy sky conditions based on satellite remote sensing data. Background technique [0002] The air temperature near the surface usually refers to the atmospheric temperature measured by the shutter box of the meteorological station 1.5 meters above the ground, and the air temperature near the surface is one of the routine observation items of the meteorological station. Near-surface temperature is an important parameter that affects climate change, hydrology, agricultural production, drought, and residential energy consumption. High-resolution near-surface temperature information is also one of the key input parameters for many land surface processes and climate models. At present, near-surface temperature observations are mainly obtained by conventional observations at meteorological stations. Althoug...

AI Technical Summary

Problems solved by technology

[0005] Although satellite microwave observations can be used to obtain near-surface air temperature estimates under cloudy conditions, the radiation signal of the microwave channel of the earth-atmosphere system is very weak due to the long microwave wavelength, which leads to a very low spatial resolution of the microwave channel. It is less than 32 kilometers, which makes it difficult for the spatial resolution of near-surface air temperature obtained based on satellite microwave observation data to meet the needs of scientific research and practical operations

In addition, the emissivity of microwave channels of various surface types on the earth varies greatly, ranging from 0.3 to 1.0, which directly makes the estimation accuracy of near-surface air temperature based on microwave brightness temperature highly dependent on the accuracy of microwave surface emissivity. The estimation of near-surface air temperature based on microwave brightness temperature has a very large uncertainty, so the accuracy of near-surface air temperature estimation based on microwave brightness temperature is difficult to be better than 3.0K

Images