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Snow Dataset Inventory

Here is an inventory of satellite-derived, in situ, and analysis/reanalysis snow datasets, compiled by the Snow Watch Team as of 23 February 2015. This inventory of snow cover datasets was compiled following a recommendation of the GCW Snow-Watch meeting in Toronto, January 2013. The workshop highlighted the need for an up-to-date and comprehensive inventory of snow cover datasets in light of the significant increases in sources of snow cover information over the past decade. The inventory is provided in three categories: (1) Satellite-derived snow products and datasets, (2) Analyses, reanalyses and reanalysis-driven snow products and datasets, and (3) In-situ snow products and datasets. A dataset must be freely available online, represent an important source of information, and have supporting English documentation to be included in the inventory. The inventory is meant as a living document with updates and additions incorporated on an ongoing basis. To change, update or add datasets to the inventory please e-mail the required information to Ross Brown (ross.brown at ec.gc.ca).

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Product(s)
Type
Organization
Description
Period
Areal Coverage
Resolution
Variables
Frequency
Data Sources
Comments
References
Dataset Location
Contact
GlobSnow SWE
Satellite
ESA, Finnish Meteorological Institute (FMI)
Combination of climate station snow depth observations and forward microwave emission model simulations with SMMR and SSM/I satellite passive microwave data
1979-
Non-alpine Northern Hemisphere
25 km
SWE
Daily; weekly; monthly
SMMR; SSM/I; AMSR-E; SSM/I-S
Evaluation with surface obs over Eurasia gave an RMSE of 30 to 40mm for SWE values below 150 mm; systematically underestimates SWE for snowpacks > 150 mm; SWE masked out over areas with complex topography, glaciers and ice sheets
Takala et al., 2011
http://www.globsnow.info
Kari Luojus (kari.luojus@fmi.fi)
GlobSnow Snow Extent
Satellite
ESA, Finnish Meteorological Institute (FMI)
Estimation of fractional snow covered area from SCAmod algorithm
1995-
Northern Hemisphere
0.01 deg
Fractional Snow Cover
Daily; weekly; monthly
ERS-2/ATSR-2 and EnviSat/AATSR
Global daily coverage not possible due to narrow swath width of AATSR; snow cover fraction may be overestimated over very dense forest due to low reflectance dynamics
Metsmki et al. 2015
http://www.globsnow.info
Sari Metsmki (sari.metsamaki@ymparisto.fi)
NASA Standard AMSR-E
Satellite
NASA
19 and 37 GHz Tb difference; enhancements for vegetation and grain size evolution; distinction between shallow and deep snow
2002-2011
Northern Hemisphere
25 km
SWE
Daily; pentad; monthly
AMSR-E, AMSR2
Kelly, 2009
http://nsidc.org/data/docs/daac/ae_swe_ease-grids.gd.html
Marco Tedesco (cryocity@gmail.com)
NASA Prototype AMSR-E
Satellite
NASA
Combination of numerical techniques, snow emission modeling and climatology
2002-2011
Northern Hemisphere
25 km
SWE
Daily; monthly
AMSR-E
Marco Tedesco (cryocity@gmail.com)
NOAA AMSR2 Snow Products
Satellite
NOAA
Variation of NASA AMSR-E methodology
2014-
Global
25 km
Snow Cover, Depth, SWE
Daily
AMSR2
This is a new set of products that is generated routinely at CIMSS/University of Wisconsin, but will not be operational in NOAA until later in 2015
Yong-Keun Lee (yklee@ssec.wisc.edu) or Jeff Key (jeff.key@noaa.gov)
JAXA AMSR2 Snow Products
Satellite
JAXA
Rosenkrantz (1998) (11 yr RAOB + RT)
2012-
Near-global (daily)
10 & 25 km, swath
Snow Cover, SWE, SD
Daily
AMSR2 (18, 36, 10 23 GHz)
http://gcom-w1.jaxa.jp (V1 product)
Richard Kelly (rejkelly@uwaterloo.ca)
US National Ice Center Operational Global Snow Products (IMS)
Satellite
NIC
Trained analyst interpretation of satellite imagery and derived mapped products
IMS 24 km 1997-, IMS 4 km 2004-, IMS 1 km 2015-
Northern Hemisphere, Global
1 km, 4 km, 24 km
snow /no snow
Daily
AVHRR, MODIS, GOES, SSMI, as well as derived mapped products (USAF Snow/Ice Analysis, AMSU, AMSR-E, NCEP models, etc.) and surface observations
Ramsay 1998; Helfrich et al. 2007
http://www.natice.noaa.gov/ims/
Sean Helfrich (sean.helfrich@noaa.gov)
Global 4KM Multisensor Automated Snow/Ice Map Product (GMASI)
Satellite
NOAA NESDIS
Combined optical and microwave retrievals with recurrent gap filling to maintain data continuity
2006-
Global
4 km
snow / no snow
Daily
MetOp AVHRR, MSG SEVIRI, GOES Imager and DMSP SSMIS
http://www.star.nesdis.noaa.gov/smcd/emb/snow/documents/Global_Auto_Snow-Ice_4km_ATBD_February_2014.pdf
Maps: http://satepsanone.nesdis.noaa.gov/; Data: contact PI
Peter Romanov (peter.romanov@noaa.gov)
CryoClim Multi-Sensor Snow Cover Product
Satellite
ESA, Norwegian Computing Centre, Norwegian Met. Inst.
Combined optical and microwave fusion with SCE estimation based on Hidden Markov Model approach
1982-
Northern Hemisphere
5 km
snow / no snow
Daily, monthly, annual
SMMR, SSM/I, AVHRR GAC
An update of the dataset will take place in 2015/16 together with a more comprehensive validation
http://www.cryoclim.net
http://www.cryoclim.net/cryoclim/subsites/data_portal/
Rune Solberg (rune.solberg@nr.no)
Cryoland PanEuropean Fractional Snow Extent Product
Satellite
ESA, ENVEO
Snow cover fraction estimated from NDSI thresholding
Nov 2000-
Pan-European Domain; 35-72N 11-50E
~500 m
Fractional Snow Cover and uncertainty
Daily (latency < 1 day)
MODIS (VIIRS; Sentinel-3)
Some misclassification of patchy snow in spring/summer related to MODIS Cloud Product; larger uncertainties in rugged terrain as only one band is used in the snow cover calculations
not specified
http://cryoland.eu
Thomas Nagler (Thomas.nagler@enveo.at)
European Alps AVHRR SE dataset
Satellite
Remote Sensing Research Group, University of Bern, Switzerland
1 km snow extent climatology for the Alpine region derived from AVHRR data over the period 19852011
1985-2014
European Alps + Europe
1 km
snow / no snow
AVHRR
Hsler et al (2014), Hsler, et al (2012)
http://www.geography.unibe.ch/content/forschungsgruppen/fernerkundung/forschung/globsnow/index_eng.html
Stefan Wunderle (Stefan.wunderle@giub.unibe.ch)
EURACSnowAlps
Satellite
Institute for Applied Remote Sensing, EURAC, Bolzano, Italy
Higher resolution snow cover estimates from MODIS using topographic correction for MODIS bands
2002-
European Alpine Arch (43-48N, 5-15E)
250 m
Fractional snow cover
Daily
MODIS, band 1 (RED) and band 2 (NIR) (for snow)
Improved mapping of snow in mountain regions compared to standard MODIS products especially patchy snow; Topographic correction cannot eliminate completely shadow effect in very steep slope especially during the morning acquisition (TERRA);Some limitations in detecting snow in forested areas; Some misclassification of snow-cloud
Notarnicola et al. (2013)
webgis.eurac.edu/snowalps/
Claudia Notarnicola (claudia.notarnicola@eurac.edu)
Japanese Global Snow Cover Extent for Climate Dataset (GHRM5C)
Satellite
JAXA (Japan Aerospace Exploration Agency)
Estimate of global SCE from 5 channels of AVHRR and MODIS to create climate record from 1979
1979-2013
Global
0.05 deg
snow / no snow / wet snow
Daily, weekly, monthly
AVHRR (1979-2000), MODIS (2000-2013)
Higher resolution coverage than NOAA CDR product; Discriminates between dry and wet snow; Some missing months in 1980, 1981, 1994, 1995, 2001; Values over Antarctic are not valid; degraded performance in dense forest, cold desert and high mountains
not specified
http://kuroshio.eorc.jaxa.jp/JASMES/index.html
Masahiro Hori (EORC/JAXA) (hori.masahiro@jaxa.jp)
MODIS Snow Products Collection 6
Satellite
NASA Goddard
Snow cover fraction estimated from the spectral characteristics of reflected solar energy. Daily data are cloud gap filled.
Terra: 24 Feb 2000- Aqua: 4 July 2007-
Global
500 m swath; 0.05 by 0.05
Snow cover fraction (%), cloud persistence count, QA assessment
day, 8-day, month
MODIS bands 1,2,4,6
More accurate mapping of spring and summer snow cover in mountainous areas achieved by removing the surface temperature screen
Hall, D. K., V. V. Salomonson, and G. A. Riggs. 2006.
NSIDC
Dorothy Hall (Dorothy.K.Hall@nasa.gov)
MODIS MODSCAG Products
Satellite
NASA JPL
Snow cover fraction estimated from spectral mixture analysis MODSCAG method
March 2000-
Global
Snow cover fraction (%)
Research Dataset
TERRA, AQUA
Painter et al. (2009)
http://snow.jpl.nasa.gov/portal/browse/dataset/urn:snow:MODSCAG
Tom Painter (Tom.Painter@jpl.nasa.gov)
NOAA-CDR
Satellite
Rutgers University, NOAA, NCDC
89 x 89 Polar Stereographic grid (190.5 km spacing)
1966- Some missing months in 1966-1971 period
Northern Hemisphere
190.5 km
snow presence/absence based on 50% snow cover threshold (weekly); snow cover duration fraction % (monthly)
weekly, monthly
Mainly visible imagery (VHRR, AVHRR, VISSR, VAS); Based on IMS 24 km from June 1999-
Data extensively used for climate monitoring (e.g. IPCC, BAMS State of Climate), model evaluation and snow cover-climate studies. Mainly recommended for continental-hemispheric scale studies. Changes in charting procedures and satellite resolution and frequency have occurred over time that may impact data homogeneity. Note that the monthly snow cover fraction is a duration fraction not an areal fraction.
Robinson et al. (2012) NOAA National Climatic Data Center. doi:10.7289/V5N014G9; Robinson et al. (1993); Estilow et al. (2013)
http://climate.rutgers.edu/snowcover/
David Robinson (david.robinsonrobins@rci.rutgers.edu); Thomas Estilow (thomas.estilowesti@rci.rutgers.edu)
MEaSUREs Northern Hemisphere Terrestrial Snow Cover Extent Daily 25km EASE-Grid 2.0
Satellite
NSIDC
Snow cover presence/absence from three satellite sources plus a merged source estimate
1999 2012; MODIS in 2000-2012 period
Northern Hemisphere
25 km
snow cover presence/absence
daily
IMS, MODIS Collection 5 Cloud Gap Filled Snow Cover, PMW brightness temperature, merged estimate
Robinson et al (2014). NSIDC. DOI: 10.5067/MEASURES/CRYOSPHERE/nsidc-0530.001 ; http://nsidc.org/data/docs/measures/nsidc-0530/index.html#data_description
ftp://sidads.colorado.edu/pub/DATASETS/nsidc0530_MEASURES_nhsnow_daily25/
Hall, Robinson and Mote nsidc@nsidc.org
MEaSUREs Northern Hemisphere Terrestrial Snow Cover Extent Weekly 100km EASE-Grid 2.0
Satellite
NSIDC
Snow cover presence/absence from two satellite sources plus a merged source estimate
1966-2012; PMW in 1979-2012 period
Northern Hemisphere
100 km
Snow cover presence/absence
weekly
NOAA-CDR, PMW brightness temperature, merged estimate
Robinson et al (2014). NSIDC. DOI: 10.5067/MEASURES/CRYOSPHERE/nsidc-0531.001; http://nsidc.org/data/docs/measures/nsidc-0531/index.html#data_description
ftp://sidads.colorado.edu/pub/DATASETS/nsidc0531_MEASURES_nhsnow_weekly100/
Robinson and Mote; nsidc@nsidc.org
GRACE
Satellite
NASA JPL, German Space Agency, ESA, University of Texas at Austin
Area-averaged estimates of terrestrial water storage anomalies (snow + ice + soil + ground water)
March 2002-
Global
1x1 deg. and 4X4 deg. grids
Water storage anomalies (depth)
monthly
Requires expert knowledge to use these data correctly. See Frappart et al (2011) and Forman et al (2012) for examples of GRACE applications related to snow water storage.
Landerer and Swenson (2012)
Grace Products: http://podaac.jpl.nasa.gov/grace
Felix.W.Landerer@jpl.nasa.gov
Theia Snow Product
Satellite
CNES, CESBIO
Snow cover presence or absence
Nov 2015-
Western Alps, Pyrenees, Atlas (to be extended to European mountains)
20 m
snow and cloud presence or absence
5 to 10 days
Sentinel-2
Real-time data production scheduled to start in December 2017
Gascoin and Grizonnet (2017). Algorithm theoritical basis documentation for an operational snow cover extent product from Sentinel-2 and Landsat-8 data. Retrieved from http://tully.ups-tlse.fr/grizonnet/let-it-snow/b
theia.cnes.fr
Simon Gascoin (simon.gascoin@cesbio.cnes.fr)
SNODAS (SNOw Data Assimilation System); NSIDC G02158
Reanalysis
NWS/NOHRSC
Output from snow modelling and data assimilation system run at NOHRSC. Incorporates satellite data, surface observations, and output from physical snowpack model.
30 Sept 2003-
Contiguous US
30 arc seconds
SWE, SD, Snowmelt Runoff, Snowpack temperature, Sublimation, Solid/Liquid Precipitation
NSIDC archives fields representing the model state for 06:00 Universal Time (UTC).
Operational product
National Operational Hydrologic Remote Sensing Center. 2004. Snow Data Assimilation System (SNODAS) Data Products at NSIDC, Boulder, Colorado USA: National Snow and Ice Data Center. http://dx.doi.org/10.7265/N5TB14TC
http://nsidc.org/data/docs/noaa/g02158_snodas_snow_cover_model/
Andy Rost (andy.rost@noaa.gov)
Liston and Hiemstra (2011)
Reanalysis
UCAR/NCAR
SnowModel driven by 10 km downscaled MERRA output. Incorporates SnowTran blowing snow model.
1979-2009
NH land area north of ~55N
10 km
SWE
Daily
One-off research dataset
No land/sea mask provided. SWE set to zero over water points.
Liston and Hiemstra, 2011
http://data.eol.ucar.edu/codiac/dss/id=106.309
Glen Liston, (Glen.Liston@colostate.edu)
MERRA-Land Reanalysis (Catchment LSM with enhanced precip forcing)
Reanalysis
NASA
Catchment land surface model driven by MERRA's AGCM (3DVAR assimilation of mainly satellite-derived atmospheric variables, surface pressure obs and precipitation)
1979-
Global
0.5 x 0.67 deg
Snowfall, SWE, SD, Snow sfce and layer temps, Snowmelt, Fractional snow covered area
Variables available at hourly, synoptic, daily, and monthly averaging periods
Output typically updated 2-3 weeks after the end of the month
This version of MERRA-land contains a discontinuity in SWE related to changes to precip forcing.
NASA, Reichle et al. 2011
Data: http://disc.sci.gsfc.nasa.gov/daac-bin/DataHoldings.pl Variable definitions: http://gmao.gsfc.nasa.gov/products/documents/MERRA_File_Specification.pdf
Rolf Reichle, (rolf.h.reichle@nasa.gov; merra-questions@lists.nasa.gov)
MERRA Reanalysis (Catchment LSM)
Reanalysis
NASA
Catchment land surface model driven by MERRA's AGCM (3DVAR assimilation of mainly satellite-derived atmospheric variables and surface pressure obs)
1979-
Global
0.5 x 0.67 deg
Snowfall, SWE, SD, Snow sfce and layer temps, Snowmelt, Fractional snow covered area
Variables available at hourly, synoptic, daily, and monthly averaging periods
Output typically updated 2-3 weeks after the end of the month
No evidence of major discontinuities in SWE over the period
NASA, Rienecker et al., 2011
http://disc.sci.gsfc.nasa.gov/daac-bin/DataHoldings.pl
merra-questions@lists.nasa.gov
GLDAS-1 (Noah, Vic, Mosaic and CLM LSMs)
Reanalysis
Suite of land surface models driven offline by GLDAS-1 output
1979-
Global
1 x 1 deg
SWE, snow melt, snowfall rate (additional snow variables for the Vic simulation)
3-hourly, monthly
Operational product
"GLDAS-1 forcing data sources were switched several times, over the record from 1979 to present, which introduced unnatural trends and resulted in highly uncertain forcing fields in 1995-1997". (Rui and Beaudoing 2014)
NASA, Rodell et al., 2004; Online Documentation (Rui 2011): ftp://hydro1.sci.gsfc.nasa.gov/data/s4pa/GLDAS_V1/README.GLDAS.pdf
http://disc.sci.gsfc.nasa.gov/hydrology/data-holdings
http://ldas.gsfc.nasa.gov/gldas/
GLDAS-2 Reanalysis (Noah LSM)
Reanalysis
Noah land surface model driven offline by GLDAS-2 forced with the global meteorological data set from Princeton University (Sheffield et al., 2006).
1948-2010
Global
0.25 x 0.25 deg
SWE, SD, snow melt, snowfall rate, snow sfc temp
3-hourly, monthly
One-off reanalysis
Abnormally high SWE values over Greenland and other points with conditions conducive to land ice formation. These need to be masked out.
NASA, Rodell et al., 2004 ; Online documentation (Rui and Beaudoing 2014): http://hydro1.sci.gsfc.nasa.gov/data/s4pa/GLDAS/README.GLDAS2.pdf
http://disc.sci.gsfc.nasa.gov/hydrology/data-holdings
http://ldas.gsfc.nasa.gov/gldas/
Canadian Meteorological Centre (CMC) Daily Snow Depth Analysis
Reanalysis
Env. Canada
Optimal interpolation of real-time snow depth obs with first guess field generated by a snow model forced with analyzed air temp and forecast precip (Brasnett, 1999). Mean monthly SWE estimated from mean mly snow depth using mly mean snow density look-up table by snow-climate region (Brown and Mote, 2009)
Aug 01 1998 - July 31 2014
NH land area subset of global output corresponding to the 1024x1024 grid used by the IMS-24km product
The native resolution of the global analysis is ~35 km. The NH subset archived at NSIDC is interpolated to a 24 km Polar Stereographic grid
Daily SD, monthly average estimated SWE
daily, monthly average
Research subset over NH updated annually. Will be replaced in 2015 with a high resolution land data assimilation scheme using in situ and satellite obs.
Contains discontinuity in 2007 due to change in precip forecast. Quality assessment and error notes included in the online documentation at NSIDC.
Brown, Ross D. and Bruce Brasnett. 2010, updated annually. Canadian Meteorological Centre (CMC) Daily Snow Depth Analysis Data. Environment Canada, 2010. Boulder, Colorado USA: National Snow and Ice Data Center.
http://nsidc.org/data/nsidc-0447
Ross Brown (ross.brown@ec.gc.ca)
ERA-interim/Land
Reanalysis
ECMWF
HTESSEL land surface model driven by ERA-Interim + GPCP v2.1 adjustments
1979-2010
80 km
Balsamo et al., 2013
http://apps.ecmwf.int/datasets/data/interim_land/
Gianpaolo Balsamo gianpaolo.balsamo@ecmwf.int
Brown et al. 2003 historical daily snow depth analysis
Reanalysis
Env. Canada
Historical analysis of daily snow depths over NA for AMIP2 period following CMC operational global analysis of Brasnett (1999) but with air temperature and precipitation forcing from ERA-15 (TOGA used for 1994-1997 period).
1979-1997
North America
0.25 degrees
SD, estimated SWE
daily, monthly average
One-off research dataset
Advantages: provides complete spatial and temporal information; includes some QC as obs are rejected that diverge strongly from expected values. Disadvantages: subject to the biases of point snow depth measurements in open terrain; information not provided on the number of stations used to derive gridpoint values. Notes: Continental SCE agrees closely with NOAA-CDR during winter months (Nov-March) but agreement drops off quickly in the spring period. Cannot be combined with the CMC analysis dataset as the two datasets use different precipitation analyses.
Brown et al (2003)
ftp://ccrp.tor.ec.gc.ca/pub/RBrown/NA_AMIP2_Snow_Depth_and_SWE_Analysis_1979-1997/
Ross Brown (ross.brown@ec.gc.ca)
NLDAS LSM
Reanalysis
NASA
Mosaic, Vic, Noah and SAC LSMs forced with output from NLDAS-2
1979-
North America
0.125 degrees
Rui and Mocko (2014)
http://ldas.gsfc.nasa.gov/nldas/NLDAS2model_download.php
David Mocko David.Mocko@nasa.gov
NARR
Reanalysis
NCEP
Based on the Noah land surface process model and assimilated snow depths from US Air Force daily snow depth analysis
1979-2014
North America
32 km
SD, SWE, snow cover fraction, snow melt, albedo
3hr, daily, monthly
Static
Found to greatly underestimate maximum SWE compared to Brown et al. (2003) historical analysis.
Mesinger et al. (2006)
3-hourly data: ftp://ftp.cdc.noaa.gov/Datasets/NARR/
http://www.emc.ncep.noaa.gov/mmb/rreanl/
ERA-40
Reanalysis
ECMWF
Assimilation of surface snow depth observations where available. Background field generated by LSP model driven by forecast fields (Douville et al. 1995).
1957-2002
Global
2.5 degrees
SWE, snow melt, snow sublimation, snowfall
6-hourly, daily, monthly
Replaced by ERA-interim
Snow depth observations between 1992 and 1994 inadvertently omitted from analysis. Khan et al. (2008) found reasonable agreement with surface obs over Russia.
Uppala et al. (2005)
http://apps.ecmwf.int/datasets/data/era40_daily/
http://www.ecmwf.int/
ERA-Interim
Reanalysis
ECMWF
Assimilation of surface snow depth observations where available. Background field generated by LSP model driven by forecast fields (Douville et al. 1995).
1979-
Global
0.75 degrees
SWE, snow density, snow melt, snow sublimation, snow albedo, snow temperature, snowfall
6-hourly, daily, monthly
Ongoing. Updated monthly.
Documented problems with the in situ snow depth assimilation from 2003-2010. The Cressman analysis method creates unrealistic spatial patterns in mountainous and data sparse regions.
Dee et al. (2011)
http://apps.ecmwf.int/datasets/data/interim_full_daily/
http://www.ecmwf.int/
NCEP/NCAR (NCEP Reanalysis 1)
Reanalysis
NCEP
3D-Var assimilation using snow cover from NESDIS weekly charts. Snow cover capped at 100 mm.
1948-
Global
1.875 deg
SWE
6 hours
Updated daily
Snow fields not recommended for various reasons see Khan et al. (2008) and Klehmet et al. (2013).
Kalnay et al. (1996)
http://www.esrl.noaa.gov/psd/data/gridded/data.ncep.reanalysis.surfaceflux.html
http://www.esrl.noaa.gov/psd/data/reanalysis/reanalysis.shtml
NCEP/DOE (NCEP Reanalysis 2
Reanalysis
NCEP
Similar to Reanalysis-1 but allows snow accumulation from dynamic snow model.
1979-
Global
1.875 deg
SWE
6 hours
Updated annually
Found to overestimate winter SWE cf GlobSnow over Siberia in period prior to 2001 and to underestimate from 2001 (Klehmet et al. 2013). Khan et al. (2008) report poor results over Russia for 1979-2004 period.
Kanamitsu et al (2002)
http://www.esrl.noaa.gov/psd/data/gridded/data.ncep.reanalysis2.gaussian.html
http://www.esrl.noaa.gov/psd/data/gridded/data.ncep.reanalysis2.html
CFSR - Climate Forecast System Reanalysis
Reanalysis
NCEP
3DVAR assimilation using snow simulated by Noah 4-layer land surface process model, SWE obs from US Air Force daily snow depth analysis and snow cover analysis from IMS.
1979-2010; Version 2 updates from 2011
Global
0.5 degrees
Snow cover, SD, SWE
Hourly, 6-hourly, monthly
Ongoing. 1-2 month delay.
Klehmet et al. (2013) found CFSR to underestimate SWE over most of Siberia compared to GlobSnow and surface observations.
Saha et al. (2010)
http://rda.ucar.edu/pub/cfsr.html; http://rda.ucar.edu/datasets/ds093.1/
http://cfs.ncep.noaa.gov/cfsr/
JRA-25
Reanalysis
JMA
3D-Var data assimilation. Incorporates snow depth from SYNOP reports plus additional historical data from China. Snow cover extent from NOAA weekly product used prior to 1987; SSM/I-derived snow depth and snow cover used from 1987.
1979-2004
Global
~120 km
SWE, SD, snowfall
6-hourly, monthly
Replaced by JRA-55
Snow mass is not represented explicitly in the analysis. A constant snow density of 200 kg/m3 is assumed. Analyzed snow depths over Siberia prior to winter 1982/83 are too low due to omission of snow depth obs. See Onogi et al (2007) Section 4.1.2 for documentation of other snow-related issues in the analysis. Khan et al. (2008) found JRA-25 underestimated SD over most of the main Russian river basins.
Onogi et al. (2007)
Data support no longer provide by JMA; Data archived at UCAR; http://rda.ucar.edu/datasets/ds625.0/
Dave Stepaniak (303-497-1343). davestep@ucar.edu
JRA-55
Reanalysis
JMA
4D-Var data assimilation. Includes the same snow data sources as JRA-25 plus additional snow depth data over USA, Russia and Mongolia
1958-2012
Global
~60 km
SWE, SD
3-hr, 6-hr, daily, monthly
Static
Ebita et al (2011) http://jra.kishou.go.jp/JRA-55/index_en.html
3-hr, 6-hr and daily: http://rda.ucar.edu/datasets/ds628.1/; Monthly means and variances: http://rda.ucar.edu/datasets/ds628.1/
Dave Stepaniak (303-497-1343). davestep@ucar.edu
20CR (V2)
Reanalysis
NCEP
Derived snow cover information from 4-layer Noah LSP model based on assimilating only surface pressure reports with observed; monthly sea-surface temperature and sea-ice distributions as boundary conditions.
1871-2012
Gobal
2 degrees
SD, snow cover fraction
3-hourly, daily, monthly; Note: 20CR includes the mean and spread from 56 ensemble members
Updated annually
Peings et al. (2013) found 20CR provided realistic simulations of snow cover onset variability over Eurasia.
Compo et al (2011)
http://www.esrl.noaa.gov/psd/data/gridded/data.20thC_ReanV2.html
Gil Compo, Research Scientist, CIRES University of Colorado compo@colorado.edu
CanSISE
Reanalysis
Env. and Climate Change Canada
Gridded terrestrial SWE (average and spread) from 5 SWE products: GlobSnow V2, ERA-Interim/Land, MERRA, Crocus snowpack model driven by ERA-Interim, and GLDAS SWE product. See Mudryk et al. (2015) for a description of datasets and intercomparison results.
1981-2010
NH
1 degree
SWE (avg, spread)
daily
Static
Provides an indication of the uncertainty in SWE from the spread in the 5 datasets. The multi-dataset average is typically more strongly correlated with surface observations than any single dataset. The gridding process created an artificial gradient around coastlines that can be removed by setting a minimum SWE threshold ~5-10 mm.
Mudryk, L. R. and C. Derksen. 2017. CanSISE Observation-Based Ensemble of Northern Hemisphere Terrestrial Snow Water Equivalent, Version 2. [Indicate subset used]. Boulder, Colorado USA. NSIDC: National Snow and Ice
http://nsidc.org/data/NSIDC-0668
Lawrence Mudryk, Env. and Climate Change Canada, lawrence.mudryk@canada.ca
Russian Historical Snow Depth Data
In situ
RIHMI-WDC
Manual obs of daily snow depth (avg of readings from 3 fixed stakes)
1881-
Russia and Former Soviet Union
600 stations - higher density of coverage over European sector
SD; snow cover fraction
daily
Continuous measurements at most stations. Updated annually.
Bulygina et al (2011)
http://meteo.ru/english/climate/snow.php
Olga Bulygina (bulygina@meteo.ru)
Russian Historical Snow Survey Data
In situ
RIHMI-WDC
Manual snow surveys
1966-
Russia and Former Soviet Union
517 stations - higher density of coverage over European Sector
snow cover fraction, SD, SWE, ice crust presence and thickness; observations at both open and vegetated survey lines at some sites
1-3 times per month (typically every 10 days)
Continuous measurements at most stations. Updated annually.
Bulygina et al (2011)
http://meteo.ru/english/climate/snow1.php
Olga Bulygina (bulygina@meteo.ru)
Global Historical Climate Network - Daily (GHCN-D)
In situ
NOAA NCDC
Daily snow depth observation from various sources subject to a common set of QC protocols.
1763-
Mainly countries reporting real-time snow depth observations to the WMO GTS/WIS
Spatial coverage highly variable in space and time; most dense coverage over NH mid-latitudes
SD, snowfall, SWE; other climate variables such as temperature, precipitation and pressure are also included in the dataset
daily
Station numbers vary in time. Data updated in near real-time
Menne et al (2012)
ftp://ftp.ncdc.noaa.gov/pub/data/ghcn/daily/ http://www1.ncdc.noaa.gov/pub/data/ghcn/daily/
http://www.ncdc.noaa.gov/oa/climate/ghcn-daily/
Canadian Historical Snow Depth Data ("Snow Data CD")
In situ
Environment Canada
Mainly manual ruler observations (average of several measurements in open area free of drifting snow)
1900-2003
Canada
Variable spatial coverage; peak of ~2000 stations in 1980s; most data located south of ~55N
SD from predominantly manual ruler obs
daily
Variable number of stations over time; peak of ~2000 stations in 1980s; rapid fall off in station numbers either side of 1980s. Dataset not updated.
Observations are made at open, grassed sites, often at airports, that may not be representative of snow conditions in the prevailing land cover. Snow tends to melt out much earlier at these sites than surrounding areas in northern Canada.
Brown and Braaten (1998)
ftp://ccrp.tor.ec.gc.ca/pub/RBrown/Cdn_Daily_Snow_Depth_Data/
Ross Brown (ross.brown@ec.gc.ca)
Canadian Historical Snow Course Data ("Snow Data CD")
In situ
Environment Canada
Manual snow measurements of SWE from gravimetric method (MSC snow sampler)
1935-2003
Canada
Variable density; network peaks at ~2000 surveys in period 1965-1985; most data located south of ~55N
Average SD and SWE from 5-10 point snow course
bi-weekly; observations tend to be concentrated in the 2nd half of the snow season to capture annual maximum SWE
Relatively few snow courses with 30+ years of continuous measurements. Dataset not updated.
Braaten (1998)
ftp://ccrp.tor.ec.gc.ca/pub/RBrown/Cdn_Snow_Course_Data
Ross Brown (ross.brown@ec.gc.ca)
Chinese historical daily snow depth data
In situ
China Meteorological Administration, National Meteorological Information
Manual observations of daily snow depth from ruler
1951-2014 updated annually
China
212 stations (GTS stations)
SD
daily
The length of station record varies across the 212 stations but the majority of stations have more than 50 years of data in the period since 1950.
SD is reported to nearest cm. SD is set to 32700 for trace values (SD < 0.5 cm) and 32766 for missing values. Data format is described in a Readme file included in the dataset. Some stations from the tropical regions of China have entirely zero snow depths.
ftp://ccrp.tor.ec.gc.ca/pub/RBrown/China_Snow_Data
Zhifu Zhang (zzfrain@126.com); Yu Yu (yuyu@cma.gov.cn)
French Alpine snow data,
In situ
Meteo-France
Snow depth, snow properties and climate observations from mountain stations run by Meteo-France partners for avalanche risk monitoring
1971-
French Alps
156 stations
snowfall, SD, liquid water content of snowpack, snowpack density, information on snow grain size
12 hours
Operational program
https://donneespubliques.meteofrance.fr/?fond=produit&id_produit=94&id_rubrique=32
http://www.meteofrance.com/contact
Integrated Surface Database (ISD)
In situ
NCDC
The Integrated Surface Database (ISD) consists of global hourly and synoptic observations compiled from numerous sources into a single common ASCII format and common data model. ISD integrates data from over 100 original data sources, including numerous data formats that were key-entered from paper forms during the 1950s1970s time frame. http://www.ncdc.noaa.gov/isd
1902-
Global
~20,000 station; NH coverage most dense over mid-latitudes
SD, snowfall
sub-daily, daily
Smith et al (2011)
http://www.ncdc.noaa.gov/isd/data-access
http://www.ncdc.noaa.gov/contact
SNOTEL (Snow Telemetry)
In situ
Natural Resources Conservation Service (NRCS) of US Dept. of Agriculture
Automated snow depth and snow water equivalent network across the western USA and Alaska in support of water resource and flood management. Basic sites have a snow pillow, precipitation gauge and temperature sensor.
1979-
Concentrated in mountains of western USA and Alaska
853
Snow depth, SWE; additional climate observations, soil moisture and temperate at most sites
Hourly,daily, 7-day, Monthly
Online data updated in near real-time
NRCS data interface provides mainly single site access. Serreze et al (1999) developed a QCd compilation of SNOTEL data covering 1980-1998 period but it is not known if this dataset has been updated.
http://www.wcc.nrcs.usda.gov/snow/
http://www.wcc.nrcs.usda.gov/snow/snotel-wedata.html
Mike Strobel (michael.strobel@por.usda.gov)
SNOlite
In situ
Natural Resources Conservation Service (NRCS) of US Dept. of Agriculture
Automated snow depth and snow water equivalent network across the western USA and Alaska in support of water resource and flood management. Basic sites have a snow depth and temperature sensor.
2012-
Concentrated in mountains of western USA and Alaska
22 sites
Snow depth and other climatic observations
Hourly,daily, 7-day, Monthly
Online data updated in near real-time
These data compliment SNOTEL observations and replace manual/aerial observation points
http://www.wcc.nrcs.usda.gov/snow/
http://www.wcc.nrcs.usda.gov/webmap/index.html
Mike Strobel (michael.strobel@por.usda.gov)
USDA snow courses
In situ
Natural Resources Conservation Service (NRCS) of US Dept. of Agriculture
Manually measured snow courses in the Western US, Canada, and Alaska
1935--
Concentrated in mountains of western USA, Canada and Alaska
1,111 courses
SWE, SD
Monthly from January to June
Online data updated monthly
Data used for monthly water supply forecasts
http://www.wcc.nrcs.usda.gov/snow/
http://www.wcc.nrcs.usda.gov/webmap/index.html
Mike Strobel (michael.strobel@por.usda.gov)
SCAN Network
In situ
Natural Resources Conservation Service (NRCS) of US Dept. of Agriculture
Automated soil moisture/temperature stations with other climatic parameters including precipitation and air temperature. Snow depth and SWE at some sites
1991-
Across the USA and Puerto Rico and US Virgin Islands
221
SWE, SD at some sites. Mostly soil moisture/temperature and climatic parameters
Hourly, daily, 7-day, Monthly
Online data updated in near real-time
National soil moisture and soil temperature network
http://www.wcc.nrcs.usda.gov/scan/
http://www.wcc.nrcs.usda.gov/webmap/index.html
Mike Strobel (michael.strobel@por.usda.gov)
Western Italian Alps Monthly Snowfall and Snow Cover Duration, NSIDC G01186
In situ
NSIDC
Monthly snowfall amounts and monthly snow cover duration in days
1877-1996
18 stations. Available stations range from 565 meters to 2720 meters in elevation.
Snow cover duration
monthly
The period of record varies with each station, with the longest station record including data from 1877 to 1996. The average station record duration is approximately 61 years.
Mercalli and Castellano ( 1999)
http://nsidc.org/data/g01186
Morphometric Characteristics of Ice and Snow in the Arctic Basin: Aircraft Landing Observations from the Former Soviet Union, 1928-1989, NSIDC G02140
In situ
NSIDC
1928-1989
200 stations max.
SD, snow cover, density
http://nsidc.org/data/g02140
Snowfall and Snow Depth for Canada 1943-1982, NSIDC G00922
In situ
NSIDC
140 stations
Monthly snowfall, end of month SD
Most likely a sub-set of the Canadian historical snow dataset (to be confirmed) RDB
http://nsidc.org/data/G00922
Snow Survey of Great Britain
In situ
British Glaciological Society (1945-1953), Met Office (1953-2007)
Manual observation of the elevation of the local snowline (> 50% snow cover)
1945-2007
The data for Scotland are digitised; Great Britain data still paper records
145 stations in digitized dataset for Scotland
Snowline elevation
Daily (Oct-May)
Not all stations reported each year or for whole record
Example of data use: https://scottishsnow.wordpress.com/2014/11/09/derrylodge/
Spencer et al (2014)
http://badc.nerc.ac.uk/
Mike Spencer (m.spencer@ed.ac.uk)

Acronyms

AATSR

Advanced Along Track Scanning Radiometer (ESA)

AMSR-2

Advanced Microwave Scanning Radiometer on JAXA GCOM-W1 spacecraft, launched May 18, 2012. This instrument is currently operating.

AMSR-E

Advanced Microwave Scanning Radiometer on NASA's EOS Aqua spacecraft, launched May 4, 2002. The instrument stopped rotating Oct 4, 2011.

AMSU

Advanced Microwave Sounding Unit

ATSR-1/2

Along-Track Scanning Radiometer on ERS-1/2 (ESA)

Aqua

One of the two NASA MODIS satellites. The local equatorial crossing time is approximately 1:30 p.m. in an ascending node.

AVHRR

Advanced Very High Resolution Radiometer (NOAA, NESDIS)

AVHRR GAC

Global Area Coverage (reduced resolution image data processed onboard the satellite)

CDR

Climate Data Record

CMC

Canadian Meteorological Centre (Environment Canada)

ECMWF

European Centre for Medium-Range Weather Forecasts

EnviSat

Environmental Satellite (ESA)

EOS

Earth Observing System (NASA)

ERS-1/2

European Remote Sensing satellite (ESA)

ESA

European Space Agency

FMI

Finnish Meteorological Institute

GCOM-W1

Global Change Observation Mission – Water (JAXA)

GOES

Geostationary Operational Environmental Satellite system (NOAA, NESDIS)

GRACE

Gravity Recovery and Climate Experiment (NASA, German Aerospace Center)

IMS

Interactive Multisensor Snow and Ice Mapping System (NOAA, NESDIS)

INTAS-SCCONE

International Association for the promotion of co-operation with scientists from the New Independent States of the former Soviet Union — Snow Cover Changes Over Northern Eurasia

JAXA

Japan Aerospace Exploration Agency

JMA

Japan Meteorological Agency

MetOp

Series of three polar orbiting meteorological satellites operated by the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT).

MODIS

Moderate Resolution Imaging Spectroradiometer (NASA)

MODSCAG

MODIS Snow Covered Area and Grain Size method for snow cover fraction retrieval

MSG SEVIRI

Spinning Enhanced Visible and Infrared Imager on the Meteosat Second Generation satellite (ESA)

NASA

National Aeronautics and Space Administration (US)

NASA Goddard

NASA Goddard Space Flight Center, Greenbelt, MD (US)

NASA JPL

NASA Jet Propulsion Laboratory, Pasadena, CA (US)

NCAR

National Center for Atmospheric Research (US)

NCDC

National Climatic Data Center (NOAA, US)

NCEP

National Centers for Environmental Prediction (NOAA, US)

NESDIS

National Environmental Satellite, Data, and Information Service (NOAA, US)

NIC

National Ice Center (US)

NIR

Near infrared

NMIC

National Meteorological Information Center (China)

NOAA

National Oceanic and Atmospheric Administration (US)

NOHRSC

National Operational Hydrologic Remote Sensing Center (NWS, US)

NSIDC

National Snow and Ice Data Center (US)

NWS

National Weather Service (

RIHMI-WDC

All-Russia Research Institute of Hydrometeorological Information - World Data Centre

Sentinel-3

Satellite in the ESA Copernicus mission

SMMR

Scanning Multichannel Microwave Radiometer (NASA)

SSM/I

Special Sensor Microwave/Imager (NASA)

SSMIS

Special Sensor Microwave Imager Sounder (NASA)

SWE

Snow Water Equivalent

Terra

One of the two NASA MODIS satellites. The local equatorial crossing time is approximately 10:30 a.m. in a descending node.

UCAR

University Corporation for Atmospheric Research (US)

USDA

United States Department of Agriculture

VIIRS

Visible Infrared Imaging Radiometer Suite (NASA)

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