Multiyear in-situ L-band microwave radiometry of land surface processes on the Tibetan Plateau (2016-2019)

This dataset contains measurements of L-band brightness temperature by an ELBARA-III microwave radiometer in horizontal and vertical polarization, profile soil moisture and soil temperature, turbulent heat fluxes, and meteorological data from the beginning of 2016 till August 2019, while the experiment is still continuing. Auxiliary vegetation and soil texture information collected in dedicated campaigns are also reported. This dataset can be used to validate the Soil Moisture and Ocean Salinity (SMOS) and Soil Moisture Active Passive (SMAP) satellite based observations and retrievals, verify radiative transfer model assumptions and validate land surface model and reanalysis outputs, retrieve soil properties, as well as to quantify land-atmosphere exchanges of energy, water and carbon and help to reduce discrepancies and uncertainties in current Earth System Models (ESM) parameterizations. ELBARA-III horizontal and vertical brightness temperature are computed from measured radiometer voltages and calibrated internal noise temperatures. The data is reliable, and its quality is evaluated by 1) Perform ‘histogram test’ on the voltage samples (raw-data) of the detector output at sampling frequency of 800 Hz. Statistics of the histogram test showed no non-Gaussian Radio Frequency Interference (RFI) were found when ELBAR-III was operated. 2) Check the voltages at the antenna ports measured during sky measurements. Results showed close values. 3) Check the instrument internal temperature, active cold source temperature and ambient temperature. 3) Analysis the angular behaviour of the processed brightness temperatures. -Temporal resolution: 30 minutes -Spatial resolution: incident angle of observation ranges from 40° to 70° in step of 5°. The area of footprint ranges between 3.31 m^2 and 43.64 m^2 -Accuracy of Measurement: Brightness temperature, 1 K; Soil moisture, 0.001 m^3 m^-3; Soil temperature, 0.1 °C -Unit: Brightness temperature, K; Soil moisture, m^3 m^-3; Soil temperature, °C/K

0 2020-10-25

Tibetan soil carbon pool to 3 m depth (2019)

This dataset is derived from the paper: Ding, J., Wang, T., Piao, S., Smith, P., Zhang, G., Yan, Z., Ren, S., Liu, D., Wang, S., Chen, S., Dai, F., He, J., Li, Y., Liu, Y., Mao, J., Arain, A., Tian, H., Shi, X., Yang, Y., Zeng, N., & Zhao, L. (2019). The paleoclimatic footprint in the soil carbon stock of the Tibetan permafrost region. Nature Communications, 10(1), 4195. doi:10.1038/s41467-019-12214-5. This data contains R code and a new estimate of Tibetan soil carbon pool to 3 m depth, at a 0.1° spatial resolution. Previous assessments of the Tibetan soil carbon pools have relied on a collection of predictors based only on modern climate and remote sensing-based vegetation features. Here, researchers have merged modern climate and remote sensing-based methods common in previous estimates, with paleoclimate, landform and soil geochemical properties in multiple machine learning algorithms, to make a new estimate of the permafrost soil carbon pool to 3 m depth over the Tibetan Plateau, and find that the stock (38.9-34.2 Pg C) is triple that predicted by ecosystem models (11.5 ± 4.2 Pg C), which use pre-industrial climate to initialize the soil carbon pool. This study provides evidence that illustrates, for the first time, the bias caused by the lack of paleoclimate information in ecosystem models. The data contains the following fields: Longitude (°E) Latitude (°N) SOCD (0-30cm) (kg C m-2) SOCD (0-300cm) (kg C m-2) GridArea (k㎡) 3mCstcok (10^6 kg C)

0 2020-10-23

Global near-surface soil freeze/thaw state (2002-2019)

The freezing / thawing state of near surface soil represents the dormancy and activity of land surface processes. This alternation of freezing and thawing phases can cause a series of complex surface process trajectory mode mutations, and affect the water cycle processes such as soil hydrothermal characteristics, surface runoff and groundwater recharge, and also affect climate change through water and energy cycle mechanism. This data set is based on AMSR-E and amsr2 passive microwave data, using discriminant algorithm to prepare global near earth surface freeze-thaw state (spatial resolution: 0.25 °; time span: 2002-2019), data storage type: 8-bit unsigned integer (file type:. HDF5) 5) Among them: 0: water body and missing data; 1: frozen soil; 2: thawed soil; 3: precipitation; 15: perennial snow and ice sheet. It can be used to analyze the spatial distribution and trend of the global freeze-thaw cycle, such as the start / end date, freezing / thawing duration, freezing range and other indicators. It can provide data support for understanding the interaction mechanism between land surface freeze-thaw cycle and water and energy exchange process under the background of global change. For detailed naming and missing of data, please refer to the data description.

0 2020-10-21

Permafrost stability type map for Sanjiangyuan in 2010s

The permafrost stability map was created based on the classification system proposed by Guodong Cheng (1984), which mainly depended on the inter-annual variation of deep soil temperature. By using the geographical weighted regression method, many auxiliary data was fusion in the map, such as average soil temperature, snow cover days, GLASS LAI, soil texture and organic from SoilGrids250, soil moisture products from CLDAS of CMA, and FY2/EMSIP precipitation products. The permafrost stability data spatial resolution is 1km and represents the status around 2010. The following table is the permafrost stability classification system. The data format is Arcgis Raster.

0 2020-10-13

Permafrost map of China and its neighbors based on Circum-Arctic Map of Permafrost and Ground Ice Conditions (2001)

Field description: Num_code (Frozen soil attribute code) Combo (Permafrost properties) extent (Extent of frozen ground) content (Ice content) Attributes comparison are as follows: (1) Comparison table of frozen soil properties: 0 (No information) 1 - chf (Continuous permafrost extent with high ground ice content and thick overburden) 2 - dhf (Discontinuous permafrost extent with high ground ice content and thick overburden) 3 - shf (Sporadic permafrost extent with high ground ice content and thick overburden) 4 - ihf (Isolated patches of permafrost extent with high ground ice content and thick overburden) 5 - cmf (Continuous permafrost extent with medium ground ice content and thick overburden) 6 - dmf (Discontinuous permafrost extent with medium ground ice content and thick overburden) 7 - smf (Sporadic permafrost extent with medium ground ice content and thick overburden) 8 - imf (Isolated patches of permafrost extent with medium ground ice content and thick overburden) 9 - clf (Continuous permafrost extent with low ground ice content and thick overburden) 10 - dlf (Discontinuous permafrost extent with low ground ice content and thick overburden) 11 - slf (Sporadic permafrost extent with low ground ice content and thick overburden) 12 - ilf (Isolated patches of permafrost extent with low ground ice content and thick overburden) 13 - chr (Continuous permafrost extent with high ground ice content and thin overburden and exposed bedrock) 14 - dhr (Discontinuous permafrost extent with high ground ice content and thin overburden and exposed bedrock) 15 - shr (Sporadic permafrost extent with high ground ice content and thin overburden and exposed bedrock) 16 - ihr (Isolated patches of permafrost extent with high ground ice content and thin overburden and exposed bedrock) 17 - clr (Continuous permafrost extent with low ground ice content and thin overburden and exposed bedrock) 18 - dlr (Discontinuous permafrost extent with low ground ice content and thin overburden and exposed bedrock) 19 - slr (Sporadic permafrost extent with low ground ice content and thin overburden and exposed bedrock) 20 - ilr (Isolated patches of permafrost extent with low ground ice content and thin overburden and exposed bedrock) 21 - g (Glaciers) 22 - r (Relict permafrost) 23 - l (Inland lakes) 24 - o (Ocean/inland seas) 25 - ld (Land) (2) Comparison table of frozen soil scope c = continuous (90-100%) d = discontinuous (50- 90%) s = sporadic (10- 50%) i = isolated patches (0 - 10%) (3) Ice content comparison table h = high (>20% for "f" landform codes) (>10% for "r" landform codes) m = medium (10-20%) l = low (0-10%)

0 2020-10-12

Geocryological regionalization and classification map of the frozen soil in China (1:10,000,000) (2000)

These data are digitized for the Geocryological Regionalization and Classification Map of the Frozen Soil in China (1:10 million) (Guoqing Qiu et al., 2000; Youwu Zhou et al., 2000), adopting a geocryological regionalization and classification dual series system. The geocryological regionalization system and classification system are used on the same map to reflect the commonality and individuality of the formation and distribution of frozen soil at each level. The geocryological regionalization system consists of three regions of frozen soil: (1) the frozen soil region of eastern China; (2) the frozen soil region of northwestern China; and (3) the frozen soil region of southwestern China (Tibetan Plateau). Based on the three large regions, 16 regions and several subregions are further divided. In the division of the geocryological boundary in the frozen soil area, the boundary between major regions I and III mainly consults the results of Bingyuan Li (1987). The boundary between major regions II and III is the northern boundary of the Tibetan Plateau, which is the Kunlun Mountains-Altun Mountains-Northern Qilian Mountains and the piedmont line. The boundary between major regions I and II is in the area of Helan Mountain-Langshan Mountain. The boundary of the secondary region is divided by the geomorphological conditions in regions II and III. However, in region I, it is mainly divided by the ratio of the annual temperature range A to the annual mean temperature T, and the frozen depths of various regions are taken into consideration. The classification system is divided into 8 types based on the continuity of frozen soil, the time of existence of frozen soil and the seasonal frozen depth. The various classifications of boundaries are mainly taken from the "Map of Snow, Ice and Frozen Ground in China" (1:4 million) (Yafeng Shi et al., 1988) and consult some new materials, whereas the seasonal frozen soil boundary is mainly based on the weather station data. The definitions of each classification are as follows: (1) Large permafrost: the continuous coefficient is 90%-70%; (2) Large-island permafrost: the continuous coefficient is 70%-30%; (3) Sparse island-shaped permafrost: the continuous coefficient is <30%; (4) Permafrost in the mountains; (5) Medium-season seasonal frozen soil: the maximum seasonal frozen depth that can be reached is >1 m; (6) Shallow seasonal frozen soil: the maximum seasonal frozen depth that can be reached is <1 m; (7) Short-term frozen soil: less than one month of storage time; and (8) Nonfrozen soil. According to the data, China's permafrost areas sum to approximately 2.19 × 106 km², accounting for 22.83% of China's territory. Among those areas, the mountain permafrost is found over 0.42×106 km2, which is 4.39% of the territory of China. The seasonal frozen soil area is approximately 4.76×106 km², accounting for 49.6% of China's territory, and the instantaneous frozen soil area is approximately 1.86×106 km², i.e., 19.33% of China's territory. For more information, please see the references (Youwu Zhou et al., 2000).

0 2020-10-09

The dataset of spatio-temporal water resources distribution in the source regions of Yangtze River and Yellow River (1998-2017)

This data is a simulated output data set of 5km monthly hydrological data obtained by establishing the WEB-DHM distributed hydrological model of the source regions of Yangtze River and Yellow River, using temperature, precipitation and pressure as input data, and GAME-TIBET data as verification data. The dataset includes grid runoff and evaporation (if the evaporation is less than 0, it means deposition; if the runoff is less than 0, it means that the precipitation in the month is less than evaporation). This data is a model based on the WEB-DHM distributed hydrological model, and established by using temperature, and precipitation (from itp-forcing and CMA) as input data, GLASS, MODIA, AVHRR as vegetation data, and SOILGRID and FAO as soil parameters. And by the calibration and verification of runoff,soil temperature and soil humidity, the 5 km monthly grid runoff and evaporation in the source regions of Yangtze River and Yellow River from 1998 to 2017 was obtained. If asc can't open normally in arcmap, please delete the blacks space of the top 5 lines of the asc file.

0 2020-10-01

Meteorological Datasets of Xidatan station (XDT) on the Tibetan Plateau in 2014-2018

This dataset is Meteorologic Elements Dataset of XDT on Qinghai-Tibet Plateau 2014-2018. Meteorologic elements including: 2m air temperature(℃), 2m air humidity(%), precipitation(mm), 2m wind speed(m/s), global radiation(w/㎡). The data are from the XiDaTan monitoring site(site code: XDTMS) of Cryosphere Research Station on Qinghai-Tibat Plateau, Chinese Academy of Sciences(CRS-CAS). These daily data was calculated from the original monitoring data(monitoring frequency is 30min). The missing part of the daily data was marked by NAN, which were manually collated and verified. The missing period was from 2017-7-7 to 2017-10-3.

0 2020-09-23

Distribution data of underground ice in permafrost regions of Qilian Mountains (2013-2015)

This data set is the distribution data of permafrost and underground ice in Qilian Mountains. Based on the existing borehole data, combined with the Quaternary sedimentary type distribution data and land use data in Qilian mountain area, this paper estimates the distribution of underground ice from permafrost upper limit to 10 m depth underground. In this data set, 374 boreholes in Qilian mountain area are used, and the indication function of Quaternary sedimentary type to underground ice storage is considered, so it has certain reliability. This data has a certain scientific value for the study of permafrost and water resources in Qilian Mountains. In addition, it has a certain promotion value for the estimation of underground ice reserves in the whole Qinghai Tibet Plateau.

0 2020-09-18

Distribution data of permafrost in the source area of the Yellow River (2013-2015)

The distribution data of permafrost in the source area of the Yellow River is established based on the annual average ground temperature model of permafrost in the source area of the Yellow River. The annual average ground temperature of 0 ℃ is taken as the standard and boundary for dividing seasonal frozen soil and permafrost. Compared with the available permafrost maps of the source region of the Yellow River (1:3 million) and the permafrost background survey project of the Qinghai Tibet Plateau (1:1 million), the data set is based on the measured data of the Yellow River source area, which has higher consistency with the measured data, and the simulation accuracy of the permafrost distribution map is the highest. The data set can be used to verify the distribution of permafrost in the source area of the Yellow River, as well as to study the frozen soil environment.

0 2020-09-18