Near-surface air temperature variability and the reliability of temperature extrapolation within glacierized regions are important issues for hydrological and glaciological studies that remain elusive because of the scarcity of high-elevation observations. Based on air temperature data in 2019 collected from 12 automatic weather stations, 43 temperature loggers and 6 national meteorological stations in six different catchments, this study presents air temperature variability in different glacierized/nonglacierized regions and assesses the robustness of different temperature extrapolations to reduce errors in melt estimation. The results show high spatial variability in temperature lapse rates (LRs) in different climatic contexts, with the steepest LRs located on the cold-dry northwestern Tibetan Plateau and the lowest LRs located on the warm-humid monsoonal-influenced southeastern Tibetan Plateau. Near-surface air temperatures in high-elevation glacierized regions of the western and central Tibetan Plateau are less influenced by katabatic winds and thus can be linearly extrapolated from off-glacier records. In contrast, the local katabatic winds prevailing on the temperate glaciers of the southeastern Tibetan Plateau exert pronounced cooling effects on the ambient air temperature, and thus, on-glacier air temperatures are significantly lower than that in elevation-equivalent nonglacierized regions. Consequently, linear temperature extrapolation from low-elevation nonglacierized stations may lead to as much as 40% overestimation of positive degree days, particularly with respect to large glaciers with a long flowline distances and significant cooling effects. These findings provide noteworthy evidence that the different LRs and relevant cooling effects on high-elevation glaciers under distinct climatic regimes should be carefully accounted for when estimating glacier melting on the Tibetan Plateau.
0 2022-04-18
This data set records the statistical data of per capita GDP and growth rate and ranking (2010-2018) of all regions in China, and the data are divided by year. The data are collected from the statistical yearbook of Qinghai Province issued by the Bureau of statistics of Qinghai Province. The data set contains eight data tables, each of which has the same structure. For example, the data table of 2017-2018 has four fields: Field 1: Region Field 2: quantity Field 3: Rank Field 4: growth rate
0 2022-04-18
The data products of mixed soil moisture of the Tibetan Plateau utilize remote sensing observation, in situ measurement and model simulation techniques. In situ soil moisture (SM) observation combines the classification of the Tibetan Plateau climate zone and is used to generate in situ measurements of SM climatology at plateau scales. The resulting in situ SM climatology of the Tibetan Plateau scale is used to scale the SM data simulated by the model, which are then used to scale the SM satellite observations. The climatological-scale satellites and model-simulated SMs are then objectively mixed by applying triple configuration and least square matching. The final mixed SM can replicate SM dynamics in different climate zones, from subhumid areas to semiarid and arid regions of the Tibetan Plateau. - Time resolution: day, starting from 01/05/2008 - Spatial resolution: 0.25° × 0.25° - Data set size: 61 × 121 × 975 - Unit: cm^3 cm^-3 The data quality is open to assessment.
0 2022-04-18
The 0.25 Degree climate data set in the northeastern part of the Tibetan Plateau from 1957 to 2009 contains four meteorological elements, which are precipitation, maximum and minimum temperatures, and wind speed. The time resolution is daily. The data set contains 2400 text files, each with precipitation (the 1st column), highest (the 2nd column) and lowest (the 3rd column) temperatures and wind speed (the 4th column). Each file name contains latitude and longitude. Each file represents the four meteorological element values for the corresponding grid point (0.25*0.25 degrees). These data are formed by gridding the observation data of 81 meteorological stations in the northeast of the plateau, considering the change of meteorological conditions with the elevation. The gridding methods and steps are as follows. Download the original daily maximum and minimum temperatures, precipitation, and wind speed from the China Meteorological Data Network (http://data.cma.cn). Then, perform quality control on the data. The principle used is 1) to remove daily precipitations below 0 and greater than 150 mm, daily temperatures below -50 °C and greater than 50 °C and wind speeds below 0 m / s, 2) draw annual sequence precipitation, temperature and wind speed, check for abnormal year-to-year changes, and conduct quality control through station migration records. For data with abnormal changes but with station migration records, the data are segmented by modifying the station name. For example, at Xining Station (52866), abnormal temperature changes occurred in 1996, which was found through records that Xining Station migrated after 1996. Therefore, the records before 1996 are recorded as virtual station 52867 data, and after 1996, the data are still recorded as 52866 stations. If the data change abnormally but there is no station migration record, the abnormally changed data are eliminated, for example, the data from Delingha Station before 1975. Some stations have migration records, but the data do not change abnormally; then, it is assumed that the stations before and after the migration are still in the same climate environment, so there is no change in station name and data record. Interpolation begins after quality control. The method begins with (1) calculating the changes in daily average temperature, precipitation and wind speed as the altitude changes. It is concluded that the temperature decreases with altitude by 4.3 °C/km, and the coefficient of determination R2 is 0.65. In the warm and humid season (from May to September), the average daily precipitation has an insignificant increase with altitude (0.5 mm/km, R2 is 0.1). The average daily precipitation in the cold dry season (from October to April) does not change with altitude. The wind speed also has an insignificant increase with altitude, with an increase rate of 0.4 m/s/km and R2 of 0.1. (2) The spatial interpolation is performed using the Synographic Mapping System (SYMAP, Shepard, 1984) method. In this method, the distance between stations and the angle between surrounding stations are taken into account in interpolation to indicate the density of stations. The distance and angle are integrated into a weight. In addition, the stations that are close and have a large angle between each other are given a large weight. (3) The latitude and longitude of the station, the meteorological element value, the altitude, the rate of change with the altitude, and the weight are considered simultaneously, and the value of the target grid is interpolated. The maximum search range for interpolation is 55 stations around, and the smallest search range is 4 stations around. (4) Integrate the precipitation in the warm and dry seasons to form a precipitation sequence throughout the period. (5) During the method test period, some stations are set aside to check the gridded data. (6) After the verification is passed, all 81 stations are used in the final gridding process and form this set of data sets. Shepard, D. S., 1984: Computer Mapping: The SYMAP interpolation algorithm. Spatial Statistics and Models, G.Gaile and C. Willmot, Eds., Reidel 133-145.
0 2022-04-18
Based on a large number of measured aboveground biomass data of grassland, the temperate grassland types were divided according to the vegetation type map of China in 1980s Based on the Landsat remote sensing data of engine platform, the random forest model of grassland aboveground biomass and remote sensing data was constructed for different grassland types. On the basis of reliable verification, the annual aboveground biomass of grassland from 1993 to 2019 was estimated, and the annual spatial data set of aboveground biomass of temperate grassland in Northern China from 1993 to 2019 was formed. Aboveground biomass is defined as the total amount of organic matter of vegetation living above the ground in unit area. The original grid value has been multiplied by a factor of 100, unit: 0.01 g / m2 (g / m2). This data set can provide a scientific basis for the dynamic monitoring and evaluation of temperate grassland resources and ecological environment in northern China.
0 2021-01-27
Based on a large number of measured aboveground biomass data of grassland, the temperate grassland types were divided according to the vegetation type map of China in 1980s Based on the Landsat remote sensing data of engine platform, the random forest model of grassland aboveground biomass and remote sensing data was constructed for different grassland types. On the basis of reliable verification, the annual aboveground biomass of grassland from 1993 to 2019 was estimated, and the annual spatial data set of aboveground biomass of temperate grassland in Northern China from 1993 to 2019 was formed. Aboveground biomass is defined as the total amount of organic matter of vegetation living above the ground in unit area. The original grid value has been multiplied by a factor of 100, unit: 0.01 g / m2 (g / m2). This data set can provide a scientific basis for the dynamic monitoring and evaluation of temperate grassland resources and ecological environment in northern China.
0 2022-04-18
The distribution data of Central Asia desert oil and gas fields are in the form of vector data in ". SHP". Including the distribution of oil and gas fields and major urban settlements in the five Central Asian countries. The data is extracted and cut from modis-mcd12q product. The spatial resolution of the product is 500 m, and the time resolution is 1 year. IGBP global vegetation classification scheme is adopted as the classification standard. The scheme is divided into 17 land cover types, among which the urban data uses the construction and urban land in the scheme. The data can provide data support for the assessment and prevention of sandstorm disasters in Central Asia desert oil and gas fields and green town.
0 2022-04-18
The atmospheric forcing dataset for along the Belt and Road from 2000 to 2015 comes from CRUNCEP. CRUNCEP is an atmospheric forcing dataset used forcing the land surface models. Specifically, this long time series data set (including temperature, precipitation, temperature, etc.) is used to drive the Community Land Model (CLM) Land Model in the long term. The CRUNCEP is a combination of two existing datasets; the CRU TS3.2 0.5 X 0.5 monthly data covering the period 1901 to 2002 and the NCEP reanalysis 2.5 X 2.5 degree 6-hourly data covering the period 1948 to 2016. The CRUNCEP dataset has been used to force CLM for studies of vegetation growth, evapotranspiration, and gross primary production and for the TRENDY (trends in net land-atmosphere carbon exchange over the period 1980-2010) project, among many other use cases. The CRUNCEP data archived in this dataset is Version 7.
0 2022-04-18
This data set includes grid emission inventories of sulfur dioxide, nitrogen oxides and PM2.5 in 2019 in China's third polar region (Tibet, Xinjiang, Yunnan and Qinghai). The emission inventory comes from the emission inventory database of the research group of Professor Wang Shuxiao of Tsinghua University. The emission inventory is processed into a 1km * 1km grid dataset by using ArcGIS software technology. The basic data of emission calculation is calculated by the emission factor method based on public data collection, satellite observation data and literature collection. The data are from the data of the National Bureau of statistics and the statistical yearbook of other industries, and its quality can be guaranteed. The data can be used for further study of climate and air quality in the third polar region.
0 2022-04-18
In order to investigate the variation characteristics of agricultural water resources vulnerability in Central Asia, an index system was established with 18 indicators from three components, namely exposure, sensitivity and adaptation, according to the scheme of vulnerability assessment. Based on the socio-economic, topography, land cover and soil data, agricultural water resources vulnerability were calculated using the Equal-Weights and Principal Component Analysis (PCA) method. Each original raster data is resampled, starting from the upper-left corner of the original grid, and extending to the adjacent right and lower grids in turn, and every four grids (0.5 °) are merged into one grid, taking the median data as the center point value corresponding to four grid of geographic coordinates. The extreme values of the grids could be eliminated. The data sets includes 1992-1996, 1997-2001, 2002-2006, 2007-2011, 2012-2017and 1992-2017with a spatial resolution of 0.5°*0.5°. It is expected to provide basic data support for agricultural water supply and demand, development and utilization analysis in five central Asian countries.
0 2022-04-18
1) Data content (including elements and meanings): Gridded multiyear-average monthly air temperature lapse rate data over the Tibetan Plateau at three kinds of resolutions (i.e. 0.25°, 0.75° and 2°) 2) Data source and processing method: Locally reliable temperature lapse rates are created from filtered MODIS LST-elevation samples by using the thresholds of standard error of elevation and correlation coefficient 3) Data quality description: For ERA-Interim, the validation accuracy (based on 1980-2014 daily mean aire temperature records from 113 stations across the Tibetan Plateau) decreases from ~4℃ to ~2℃ after using the 0.75° temperaturel lapse rate. 4) Data application results and prospects: This dataset can be used for downscaling air temperature from multiple reanalysis datasets.
0 2022-04-18
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