FCover provides the longest time series (1999-present) at 1 km, although since 2014 this dataset is also available at 300 m. Various datasets provide information on the cover fraction for long periods of time at medium and high spatial resolutions. The Forests of the World 2010 is also available for just one year (2010), albeit at a more detailed spatial resolution (250 m). Among the maps providing information on the fraction of vegetation cover per pixel, the Hybrid Forest Mask 2000 (1 km) and the PTC Global Version (500 m–1 km) offer relatively coarse resolutions and few points in time: just one date in the former (2000) and two in the latter (2003, 2008). SYNMAP is a very specific thematic map designed to meet the needs of the carbon cycle and vegetation modelling community, which was produced at a spatial resolution of 1 km and with a legend of 48 categories. Of all the products reviewed here, the World’s Forests 2000 is probably the most basic, providing information about three wooded cover categories for the year 1995/96 at a spatial resolution of 1 km. ![]() It is not included in this review because of its high specificity, which means it is only of interest to certain communities of users. A specific dataset has been found that maps mangrove distribution across the globe at 30 m for one date (1997/00). In thematic terms, most of the maps provide information on the vegetation or tree cover fraction per pixel, so characterizing the vegetation covers on Earth in great detail. In this chapter, we review eleven of these datasets, most of which provide long series of LUC maps, so permitting the study of LUC change. A wide variety of thematic LUC datasets characterizing vegetation covers are currently available. Interest in this subject has remained strong since then because of the valuable information that these datasets provide for monitoring forests, deforestation and climate change, among other issues. Vegetation covers were one of the first land covers to receive special attention when thematic Land Use Cover (LUC) maps first appeared. The DISCover map, in general, has more forest, while the UMd map has considerably more area in the intermediate tree cover classes of woody savanna/ woodland and savanna/wooded grassland. The absence of the cropland mosaic class creates a difficulty in comparing the maps, due to its significant extent in the DISCover map. Comparison of the maps at a nominal 0.5 resolution with two global ground-based maps shows an improvement of thematic concurrency of 46% when viewing average class agreement. ![]() Individual class agreement between the two 1 km maps is 49%. This results in high regional variability between the maps. For broad vegetation types, core areas map similarly, while transition zones around core areas differ significantly. For tall versus short/no vegetation, the per-pixel agreement is 84%. Global area totals of aggregated vegetation types are very similar and have a per-pixel agreement of 74%. The DISCover map uses the IGBP classification scheme, while the UMd map employs a modified IGBP scheme minus the classes of permanent wetlands, cropland/natural vegetation mosaic and ice and snow. The UMd approach employed a supervised classification tree method in which temporal metrics derived from all AVHRR bands and the NDVI were used to predict class membership across the entire globe. The DISCover methodology employed an unsupervised clustering classification scheme on a per-continent basis using 12 monthly maximum NDVI composites as inputs. This paper makes a preliminary comparison of the methodologies and results of the two products. ![]() Below are tables which show the scheduled increases: Employers with 15 or More Employees DateĮmployers with 14 or Fewer Employees DateĪs a result of this veto override, there will likely be increased pressure on other states to follow suit and raise the minimum wage to the $15 level.Two global 1 km land cover data sets derived from 1992-1993 Advanced Very High Resolution Radiometer (AVHRR) data are currently available, the International Geosphere-Biosphere Programme Data and Information System (IGBP-DIS) DISCover and the University of Maryland (UMd) 1 km land cover maps. ![]() Smaller companies, with fewer than 15 employees have until 2026 to comply with the law. Under the bill, companies with 15 or more employees must pay workers at least $15 an hour by 2025. The District of Columbia’s minimum wage will increase to $15 on July 1, 2020 The other states that have adopted future $15 minimum wages include California, Illinois, Massachusetts, New Jersey and New York.
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