![]() ![]() SoilGrids are available under the Open Data Base License.Ĭitation: Hengl T, Mendes de Jesus J, Heuvelink GBM, Ruiperez Gonzalez M, Kilibarda M, Blagotić A, et al. ![]() up to 50 m spatial resolution) so that increasingly more accurate, complete and consistent global soil information can be produced. Another area of future research is the development of methods for multiscale merging of SoilGrids predictions with local and/or national gridded soil products (e.g. Further development of SoilGrids could include refinement of methods to incorporate input uncertainties and derivation of posterior probability distributions (per pixel), and further automation of spatial modeling so that soil maps can be generated for potentially hundreds of soil variables. Improvements can be attributed to: (1) the use of machine learning instead of linear regression, (2) to considerable investments in preparing finer resolution covariate layers and (3) to insertion of additional soil profiles. Improvements in the relative accuracy considering the amount of variation explained, in comparison to the previous version of SoilGrids at 1 km spatial resolution, range from 60 to 230%. The results of 10–fold cross-validation show that the ensemble models explain between 56% (coarse fragments) and 83% (pH) of variation with an overall average of 61%. 150,000 soil profiles used for training and a stack of 158 remote sensing-based soil covariates (primarily derived from MODIS land products, SRTM DEM derivatives, climatic images and global landform and lithology maps), which were used to fit an ensemble of machine learning methods-random forest and gradient boosting and/or multinomial logistic regression-as implemented in the R packages ranger, xgboost, nnet and caret. SoilGrids provides global predictions for standard numeric soil properties (organic carbon, bulk density, Cation Exchange Capacity (CEC), pH, soil texture fractions and coarse fragments) at seven standard depths (0, 5, 15, 30, 60, 100 and 200 cm), in addition to predictions of depth to bedrock and distribution of soil classes based on the World Reference Base (WRB) and USDA classification systems (ca. However, Burt said this record, along with others in colonial Africa, had “serious credibility issues”.This paper describes the technical development and accuracy assessment of the most recent and improved version of the SoilGrids system at 250m resolution (June 2016 update). Some modern weather experts believe that figure is wrong, along with a number of temperature records recorded that summer.īased on the analysis of weather history, Christopher Burt, in 2016, some temperature records in the region in 1913 did not coincide with records in Death Valley.Īnother temperature record on Earth was recorded in Tunisia in 1931, which reached 55 degrees Celsius. The higher temperature, which is 56.6 degrees Celsius, is believed to have occurred a century ago in Death Valley, but that is still up for debate. The hottest temperature that was probably recorded conclusively on Earth before was 54 degrees Celsius also in Death Valley in 2013. ![]() The heat of the weather also occurred when the power went out for two days in California after a power plant was damaged on Saturday (15 August). The temperature surfaced amid a heatwave hitting the west coast of the US, an area that is expected to fuel a rise in temperatures this week. The record is currently being verified by the US National Weather Service.
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