Global peatlands play a crucial ecological and economic role and have a substantial cultural share in human history. Covering approximately 3% of the global land area, peatlands store twice as much carbon than all terrestrial biomass. However, about 10% of all peatlands are drained and hence a significant carbon source – being responsible for 5% of all anthropogenic carbon dioxide emissions . Furthermore, drainage of peatlands results in soil degradation, high risks regarding fires, land subsidence as well as water pollution . Even though the sensitivity to anthropogenic pressures and a changing climate is recognised, the global extent of peatlands is poorly understood, and the demand for rapid availability of spatially explicit and high-resolution data on status and extent of global peatlands is acuter than ever, especially under consideration of the Paris Agreement entering into force in 2020.
Although often included in global wetland databases, the recognition of peatlands in climatic contexts enhanced the integration of these into stand-alone earth system (ESM) as well as global climate (GCM) models. Using grid-based land-surfaces, GCMs, as well as ESMs, require defined locations as well as fractional covers of peatlands on model grids. Since this has so far been challenging, especially in remote areas with the occurrence of predators or diseases, peatlands were frequently overlooked in databases . However, so far three approaches have been made to map the complete global peatland distribution, each having had its innovative success-story but also challenges. The first map by Yu and colleagues in 2010  was an estimated binary map rather than a gridded product and did not include true and accurate coverage and distribution details for many regions. Another approach [5,6] used soil maps in correlation with global wetland maps, based on remote sensing data such as the Global Inundation Extent from Multi-Satellites (GIEMS) initiative , the Surface Water Microwave Product Series (SWAMPS)  as well as MODIS data from the Global Lake and Wetlands Database (GLWD-3) . Especially the latter one often led to an over-estimation of tropical peatland extents due to the lack of accurate ground-truthing for areas outside Canada, Scandinavia or Western Siberia . Furthermore, hydromorphic soils are frequently not separated into mineral and organic categories for soil mapping. The most recent global peatland inventory PEATMAP  is based on a meta-analysis of high temporal and spatial data regarding peatlands. Nonetheless, this did not result in the provision of a complete map, despite being more accurate due to the eradication of over- as well as underestimations regarding peatland extent and peat layer thickness, especially in the tropics as well as mid- and high-latitudes of the Northern Hemisphere.There is thus an urgent need for innovation in peatland mapping, respectively a better and more integrative use of novel remote sensing methods and technologies. Despite the technological progress made in mapping and monitoring the terrestrial carbon cycle using remote sensing, the spatially accurate quantification of soil carbon budgets remains underdeveloped due to the lack of temporal as well as spatial variations in vegetation physiology and phenology in many models. These difficulties regarding technical issues with vegetation – signal interferences complicated quality control methods and thus the reliability of the peatland maps produced so far . However, recent advances in remote sensing techniques, such as solar-induced chlorophyll fluorescence, sensor capabilities (including the upcoming BIOMASS and FLEX missions) as well as a rapidly increasing data pool from legacy observations offers novel opportunities to assess terrestrial carbon cycle processes. This allows developing a new approach of peatland mapping where also information regarding pedology as well as palaeoecology are taken into consideration. A new global high-resolution peatland map, combining these aspects, is expected for 2020 by a collaborative action under the leadership of the Department of Peatland Studies and Palaeoecology and the Greifswald Mire Centre, both from the University of Greifswald, Germany. The Mire Centre already coordinates the International Mire Conservation Group’s (ICGM) global peatland database which is the largest continuous data pool for distribution and status of peatlands all over the globe, based on digital peatland, soil and other proxy data per country and region. The team from Greifswald links a variety of networks, methodologies as well as databases, combining ecological and remote sensing data with legacy soil maps for successful ground-truthing . This meets the requirements to produce a high-resolution map of peatlands, being one of the most challenging land-types for accurate, high-resolution mapping , based on aggregated data from local and national peat information. This new global peatland map will combine the results from lessons-learned with recent technological and methodological advancements in GIS and remote sensing. The team’s organisation as an international network of specialists within the field, especially with local authorities and scientists from remote areas makes this new mapping approach an auspicious and exciting project to tackle this overdue issue.