31 results about "Soil heat flux" patented technology

The invention discloses a regional earth surface sensible heat / latent heat flux inversion method based on remote sensing data. The method comprises the following steps that a research area and the remote sensing data are determined; remote sensing earth surface and regional meteorological parameters are prepared according to the remote sensing data, wherein the remote sensing earth surface parameters comprise a normalized difference vegetation index NDVI, vegetation coverage f, albedo, earth surface emissivity Emiss, earth surface temperature Ts and a leaf area index LAI, and the regional meteorological parameters comprise air temperature Ta and relative humidity RH; net radiation flux Rn inversion is conducted according to the remote sensing earth surface and regional meteorological parameters; soil heat flux G inversion is conducted according to the leaf area index LAI, the air temperature Ta and net radiation flux Rn; radiation-convection impedance rae inversion is conducted according to theoretical two-dimensional space of the net radiation flux Rn, soil heat flux G, the vegetation coverage f and the earth surface temperature Ts and a temperature profile equation estimated through sensible heat flux; regional earth surface sensible heat H / latent heat LE flux inversion is achieved according to radiation-convection impedance rae.

The invention discloses a method for obtaining field evapotranspiration of field scale, comprising the following steps: S1. space registration is carried out to thermal infrared remote sensing data of original spatial resolution and visible light remote sensing data of the original spatial resolution; S2. sub-pixel temperature is calculated by utilizing the thermal infrared remote sensing data and the visible light remote sensing data whichare treated with space registration; S3. field parameters including albedo, specific emittance and vegetation coverage are calculated by utilizing the visible light remote sensing data of the original spatial resolution; S4. the field net radiation flux is calculated according to the albedo, the specific emittance and the sub-pixel temperature; S5. soilheat flux is calculated by utilizing the field net radiation flux and the vegetation coverage; and S6. the field sensible heat flux H is calculated, and the field evapotranspiration of the field scale can be calculated according to the field sensible heat flux, the field net radiation flux, the soil heat flux and field energy equilibrium equation. By adopting the method in the invention, the field evapotranspiration of the field scale can be obtained.

The invention discloses a surface water heat flux remote sensing inversion-based drought monitoring method and system. The method comprises the following steps of: calculating surface net radiation flux based on remote sensing parameter inversion, calculating soil heat flux by using an iterative calculation method, calculating sensible heat flux according to the calculation of the surface flux, calculating regional water shortage indexes (RWSI), and monitoring the regional drought degree.

The invention provides an eddy flux observation energy imbalance correction method and device, and an electronic device and relates to the meteorological monitoring technology field. By using the method, during energy imbalance correction, the flux data of a preset time scale is converted into daily-scale flux data; a Bowen ratio is used to correct the daily-scale flux data; and then, the corrected flux data of the preset time scale is obtained through the corrected daily scale data. Because a daily-scale soil heat flux is usually zero, the soil heat flux is prevented from participating in correction calculation, and a uncertainty problem generated because time or spaces between the fluxes are mismatched when energy imbalance correction is performed through directly using a Bowen ratio method in the prior art is effectively alleviated; and the effective correction of the energy imbalance phenomenon of the eddy observation flux is realized, which is beneficial to obtaining the flux dataaccording with a reality.

The invention belongs to the technical field of surface flux observation data processing, and relates to a method for interpolating missing eddy flux observation data on the ground using an ALPHA invariant method. The method of the present invention includes: constructing the input data set required by the method; aiming at the target time period in which the eddy flux observation data is partially missing, calculating the latent heat flux, soil heat flux and The average value of net radiation; based on the Priestley-Taylor equation, according to the above average value, the average ALPHA value of the corresponding time period without missing time is obtained; based on the characteristic that ALPHA remains constant, the average ALPHA value is used as the ALPHA value at the time of data loss, according to The above equation and the surface energy balance equation interpolate the flux at the time when the ground eddy flux observation data is missing. It is of great significance for the rapid and accurate estimation and verification of latent heat flux and sensible heat flux by means of remote sensing.

The invention discloses a crop biomass inversion method based on a SEBAL-HJ model. The crop biomass inversion method is characterized by comprising the following steps: S1, acquiring HJ-1 CCD, IRS images and elevation data DEM in a research plot, and carrying out geometric fine revision to the images; S2, inversing a land surface albedo, NDVI, SR, land surface emissivity and inversing land surface temperature; S3, calculating net radiation flux according to inversion results in the S2, and further calculating soil heat flux on the basis; S4, calculating sensible heat flux through cyclic reduction; S5, calculating the coefficient of evaporation ratio and obtaining evapotranspiration per day through space-time dimension expansion; S6, inversing fPAR on the basis of vegetative cover indexes NDVI and SR; S7, inversing NPP according to the inversion results of evapotranspiration per day in the step S5 and the inversion results of fPAR in the step S6; and S8, obtaining crop biomass through the accumulation of NPP after space-time reconstruction. According to the invention, the high-precision inversion of crop biomass is achieved, and the amount of calculation is relatively smaller.

The present invention provides a remote sensing estimation method and device for the intraday variation process of the surface temperature, which relates to the technical field of surface temperature remote sensing inversion. Surface net radiation data and soil heat flux data at cloudless time, remote sensing surface temperature data and vegetation index data at cloudless time; calculate evapotranspiration at cloudless time and reference evapotranspiration at cloudless time in the target area based on the above data and reference evapotranspiration at cloudy time; calculate evapotranspiration at cloudy time based on evapotranspiration at cloudless time, reference evapotranspiration at cloudless time and reference evapotranspiration at cloudy time, and calculate surface sensible heat flux at cloudy time; Sensible heat flux calculates the surface temperature at cloudy moments. The remote sensing estimation method and device for the intraday variation process of the surface temperature provided by the embodiments of the present invention can use remote sensing means to quickly obtain the intraday variation process of the surface temperature under cloudy conditions.

The invention discloses a method and system for calculating evapotranspiration based on soil heat flux, and belongs to the technical field of hydrological information forecasting. Including: obtaining the soil heat flux, surface temperature and surface air specific humidity of the target area through direct measurement by instruments or indirect calculation based on soil temperature and humidity parameters; The surface air specific humidity is input into the maximum entropy-increased evapotranspiration model, and the latent heat flux is obtained by simultaneous solution; based on the unit conversion, the latent heat flux is converted into the evapotranspiration of the target area. The invention uses the soil heat flux to measure and calculate the evapotranspiration value. By obtaining the soil heat flux instead of the net radiation item as the input of the maximum entropy increase evapotranspiration model, it avoids the dependence on the observation of radiation energy, and overcomes the difficulty of obtaining the net radiation variable, which is difficult to measure. The disadvantages of high cost and unclear error make the calculation of evapotranspiration simple and reliable.