This dataset contains permafrost extent data produced as part of the European Space Agency's (ESA) Climate Change Initiative (CCI) Permafrost project. It forms part of the first version of their Climate Research Data Package (CRDP v1). It is derived from a thermal model driven and constrained by satellite data. Grid products of CDRP v1 are released in annual files, covering the start to the end of the Julian year. This corresponds to average annual ground temperatures (at 2 m depth) which forms the basis for the retrieval of yearly fraction of permafrost-underlain and permafrost-free area within a pixel. A classification according to the IPA (International Permafrost Association) zonation delivers the well-known permafrost zones, distinguishing isolated (0-10%) sporadic (10-50%), discontinuous (50-90%) and continuous permafrost (90-100%). Case A: It covers the Northern Hemisphere (north of 30°) for the period 2003-2017 based on MODIS Land Surface temperature merged with downscaled ERA5 reanalysis near-surface air temperature data. Case B: It covers the Northern Hemisphere (north of 30°) for the period 1997-2002 based on downscaled ERA5 reanalysis near-surface air temperature data which are bias-corrected with the Case A product for the overlap period 2003-2018 using a pixel-specific statistics for each day of the year.

This dataset contains permafrost active layer thickness data produced as part of the European Space Agency's (ESA) Climate Change Initiative (CCI) Permafrost project. It forms part of the first version of their Climate Research Data Package (CRDP v1). It is derived from a thermal model driven and constrained by satellite data. Grid products of CDRP v1 are released in annual files, covering the start to the end of the Julian year. The maximum depth of seasonal thaw is provided, which corresponds to the active layer thickness. Case A: It covers the Northern Hemisphere (north of 30°) for the period 2003-2017 based on MODIS Land Surface temperature merged with downscaled ERA5 reanalysis near-surface air temperature data. Case B: It covers the Northern Hemisphere (north of 30°) for the period 1997-2002 based on downscaled ERA5 reanalysis near-surface air temperature data which are bias-corrected with the Case A product for the overlap period 2003-2018 using a pixel-specific statistics for each day of the year.

This dataset contains permafrost ground temperature data produced as part of the European Space Agency's (ESA) Climate Change Initiative (CCI) Permafrost project. It forms part of the Beta version of their Climate Research Data Package (CRDP v0). It is derived from a thermal model driven and constrained by satellite data. Grid products of CDRP v0 are released in annual files, covering the start to the end of the Julian year. This corresponds to average annual ground temperatures and is provided for specific depths (surface, 1m, 2m, 5m , 10m) for the Northern Hemisphere (north of 30°) for the period 2003-2017.

This dataset contains permafrost extent data produced as part of the European Space Agency's (ESA) Climate Change Initiative (CCI) Permafrost project. It forms part of the Beta version of their Climate Research Data Package (CRDP v0). It is derived from a thermal model driven and constrained by satellite data. Grid products of CDRP v0 are released in annual files, covering the start to the end of the Julian year. This corresponds to average annual ground temperatures which forms the basis for the retrieval of yearly fraction of permafrost-underlain and permafrost-free area within a pixel. A classification according to the IPA (International Permafrost Association) zonation delivers the well-known permafrost zones, distinguishing isolated (0-10%) sporadic (10-50%), discontinuous (50-90%) and continuous permafrost (90-100%). It covers the Northern Hemisphere (north of 30°) for the period 2003-2017.

This dataset contains permafrost active layer thickness data produced as part of the European Space Agency's (ESA) Climate Change Initiative (CCI) Permafrost project. It forms part of the beta version of their Climate Research Data Package (CRDP v0). It is derived from a thermal model driven and constrained by satellite data. Grid products of CDRP v0 are released in annual files, covering the start to the end of the Julian year. The maximum depth of seasonal thaw is provided, which corresponds to the active layer thickness. It covers the Northern Hemisphere (north of 30°) for the period 2003-2017.

This dataset contains permafrost ground temperature data produced as part of the European Space Agency's (ESA) Climate Change Initiative (CCI) Permafrost project. It forms part of the first version of their Climate Research Data Package (CRDP v1). It is derived from a thermal model driven and constrained by satellite data. Grid products of CDRP v1 are released in annual files, covering the start to the end of the Julian year. This corresponds to average annual ground temperatures and is provided for specific depths (surface, 1m, 2m, 5m , 10m). Case A: It covers the Northern Hemisphere (north of 30°) for the period 2003-2017 based on MODIS Land Surface temperature merged with downscaled ERA5 reanalysis near-surface air temperature data. Case B: It covers the Northern Hemisphere (north of 30°) for the period 1997-2002 based on downscaled ERA5 reanalysis near-surface air temperature data which are bias-corrected with the Case A product for the overlap period 2003-2018 using a pixel-specific statistics for each day of the year.

Adventdalen is a medium-sized (513 km^2) catchment in continuous permafrost zone of central Spitsbergen. It has 11.7 % glacier cover, a large flat valley floor comprised of uplifted, glaciomarine sediments, covered in the lower part by a veneer of aeolian sediments up to 4 m thick. The geology of the catchment is dominated by sandstones, shales and carbonates. There are a series of five open system pingos that have formed in the valley floor following uplift of the valley bottom over the last 10000 years. This has caused permafrost aggradation in former marine sediments which are up to 60 m thick. During the formation of this new permafrost, high pressure caused expulsion of groundwaters below, resulting in their upward migration. Freezing of the groundwaters as they reached the ground surface caused expansion and thus formation of the pingo. However, freezing no longer occurs at four of the five pingos, meaning that the groundwaters now discharge at the surface. Samples of the emerging groundwaters were collected every March/April, but also opportunistically during summer months, provided the sites weren''t flooded. Analysis of major ions (by ion chromatography), minor constituents (trace metals by inductively coupled plasma mass spectroscopy (ICP-MS) and silica by colorimetric analysis) and gases (O2, CO2 and CH4) were undertaken. Funding was provided by the Joint Programming Initiative (JPI-Climate Topic 2: Russian Arctic and Boreal Systems) Award No. 71126, distributed to Principal Investigator, Andrew Hodson (then of University of Sheffield) via NERC grant NE/M019829/1.