In the case of distributed snowmelt modeling for highelevation watersheds, swe in a gridded format is a requirement regardless of snowmelt modeling methodology water balance, energybalance, or temperature index. Station snow water equivalent reports station snowdepth reports. Sensorlogic remote sensing delivers industry leading climate change monitoring solutions. The nohrsc produces snow products and information that include estimates of. National operational hydrologic remote sensing center the. As the distance between the sensor and the snow surface decreases, the time it takes for the echo to return also decreases. Estimating snow water equivalent using snow depth data and. Problem the availability of eosera remote sensing products offers promise for improved temporal and spatial assessments of snow extent and more importantly, snow water equivalent swe, which, in the mid and highlatitudes is a critical part of the earths water and energy cycle. Projects subzero research laboratory montana state.
Snowcover reconstruction methodology for mountainous regions based on historic in situ observations and recent remote sensing data. Snow water equivalent anomaly for iraq, from famine early warning systems network fews net data portal details. Data from the visible, nearinfrared, infrared, and microwave portions of the electromagnetic spectrum have proven useful for measuring different properties of snow. Afghanistan snow water equivalent dam location snow modeling for fews net was developed and originally implemented by the noaa national operational hydrologic remote sensing center nohrsc, using a spatially distributed land surface model lsm operating within the land information system lis software framework. Product version, access, sensor, temporal coverage, spatial information. Gis data sets nohrsc the ultimate source for snow information. Snow water volume is calculated for selected basins and for basin areas upstream of specific drainage locations.
This data set contains snow pack properties, such as depth and snow water equivalent swe, from the noaa national weather services national operational hydrologic remote sensing center nohrsc snow data assimilation system snodas. Remote sensing of snow cryosphere geophysics and remote. Snow water equivalent how is snow water equivalent. The okutadami basin was superimposed with a grid and the maximum snow water equivalent was estimated by combining date of snow disappearance from landsat, degreedaytotals melt, and precipitation data.
Snow water equivalent is the estimate of the depth of liquid water contained within the snowpack. Basin areas were delineated using gis methods and a 1km digital elevation model. As global temperatures rise, the worlds snow resources are predicted to change in significant ways hosaka et al. The major characteristics of the snow cover are its height and snow water equivalent. Currently, the accurate estimation of the maximum snow water equivalent swe in mountainous areas is an important topic.
The sensor sends ultrasonic pulses downward and listens for the echo. Software titles near real time snow remote sensing processing and analysis workflow for modis and amsr2. Passive microwave pm remote sensing data have long been used to retrieve snow depth and snow water equivalent with large uncertainties. Sca is easily observable at optical visible and nearinfrared wavelengths because of the strong albedo contrast between snow covered and snowfree land. Snow water equivalent how is snow water equivalent abbreviated. Training on remote sensing of snow water resources in the. Longterm changes in global, regional, and local snow depth h s, snow water equivalent swe, and extent will ultimately have major ramifications for ecosystem function, human utilization of snow resources, and the climate itself through feedback mechanisms like snow albedo.
Jonathan munoz 1, jose infante 1, tarendra lakhankar1, reza khanbilvardi 1, peter romanov 1, nir krakauer 1 and al powell 2. Interpretation of ssmi measurements over greenland. The national weather services snow data assimilation snodas program provides daily, gridded estimates of snow depth, snow water equivalent swe, and related snow parameters at a 1km2 resolution for the conterminous usa. Unfortunately, of the three snow metrics listed above, only extent. Quantifying the uncertainty in passive microwave snow water equivalent observations. This paper presents results from a research project that determined the amount of water in a snow pack from snow depth and swe in an areal manner using remote sensing and photogrammetry. Thus, the large scale snow water equivalent information is mainly from remote sensing. Snow water equivalent swe measurements are necessary for the management of water supply and flood control systems in seasonal snowcovered regions. Clicking on the link should open and load the imagery into the client application. Synergistic use of remote sensing for snow cover and snow water equivalent estimation. Over a billion people worldwide depend on snowmelt for water supply. Snow water equivalent swe is the most important parameter used to initialize snow cover in standalone hydrology models. Marsh, title the application of remote sensing and a blowing snow model to determine snow water equivalent over northern basins, booktitle in applications of remote sensing in hydrology, kite gw, pietroniro a, pulz tj eds.
The application of remote sensing and a blowing snow model. Evaluation of passive microwave snow water equivalent retrievals across the boreal forest tundra transition of western canada. The objective of this study is to develop snowdepth retrieval algorithm based on support vector regression svr technique using pm remote sensing data and other auxiliary data. Both glaciers and snowpack form natural reservoirs that gradually release water during the drier summer months, providing drinking water and ecosystem services the varied benefits that. This survey is conducted throughout maine in the spring to aid in the evaluation of flood potential by the maine river flow advisory commission. Remote sensing is a powerful tool that offers the ability to examine quantitatively the physical properties of snow in remote or otherwise inaccessible areas where obtaining measurements may be expensive and dangerous. Accurately tracking the depth and water content swe of snow is critical to monitoring the seasonal snow pack. Remote sensing data of snow coverare now wellsuited for use in hydrologic and generalcirculationmodels. Evaluation of remotely sensed snow water equivalent and snow cover extent. Accurately tracking the depth and water content of snow is critical.
We are working with nasa to calibrate satellite data using ground based radar systems. Quantifying the relationships between lake fraction, snow. Remote sensing of snow water equivalent has been a goal of hydrologists and atmospheric scientists for many years. Airborne snow survey program nohrsc the ultimate source. By measuring the time between the pulse and its return echo, the distance between the.
Fundamemtals of hyperspectral remote sensing gis resources. Using remote sensing to estimate snow depth and snow water. Sensor logics automated lowpower snow water equivalent sensor swedar can improve forecasting of water resources for agriculture and public consumption. Swe sensors measure the amount of water contained within a snowpack. Review of snow water equivalent retrieval methods using. To monitor the state of both seasonal and perennial snow covers, several snow monitoring systems based on microwave remote sensing techniques have been deployed, but a remote sensing product that derives the snow water equivalent over various types of terrain and on a global scale, has yet to be developed. The snow cover can be identified by applying a threshold to the spectral difference.
Rao is a professor at the centre of studies in resources engineering, indian institute of technology bombay, mumbai, india. Support vector regression snowdepth retrieval algorithm. Open source toolset to download, mosaic, and merge publicly available snow covered area and snow water equivalent remote sensing datasets. Amsreaqua daily l3 global snow water equivalent easegrids.
Spatial distribution of snow cover, surface albedo and snow water equivalent. There is no remote sensing instrument to monitor snow water equivalent at useful spatial andor temporal resolutions in the hindu kush himalayan hkh region. Retrieval of water equivalent of snow cover in finland by satellite microwave radiometry. About snow water equivalent and snow depth sensors campbell scientific offers two types of sensors for snowpack applications. Units of measurement are mm, the depth of the liquid water in the vertical column. The nohrsc provides and maintains the nws integrated hydrologic automated basin boundary system ihabbs gis database to support river and flood forecasting throughout the nation. Information about snow water equivalent is needed in applications such as flood. Download gridded national snow analyses data sets for geospatial applications. However, the snow water equivalent simulated using the snow process models has large uncertainties spatially and temporally, and it may be far from the needs of practical applications.
Remote sensing of snow depth and snow water equivalent remote. May 07, 2020 snow cover is the presence of snow on land or bodies of water. The nohrsc measures snow water equivalent and soil moisture using gamma radiation remote sensing. Snow data assimilation system snodas data products at. Report dso201404 gridded snow water equivalent data set. Aso is the first remote sensing system ever to measure snow depth, snow water equivalent and snow albedo across entire mountain basins, and has uniquely quantified snow water equivalent over mountainous regions since 20. Projects subzero research laboratory montana state university.
This unique observing system includes two lowflying aircraft to conduct surveys in 31 states, including alaska, as well as in 8 canadian provinces. Jordan 1991 must be used in data assimilation schemes rather than simplified conceptual snowpack models, since estimates of several snowpack variables are required to drive the radiative transfer model see below. National operational hydrologic remote sensing center. Accurately modeling basin and catchmentscale snow water equivalent swe can quickly become a dizzying prospect as a result of such variability, but novel remote sensing techniques can provide the spatial measurement extent required to properly calibrate and validate distributed hydrologic snow models over large areas. To address this knowledge gap, the nasa servir project managing changing water resources south of the himalaya is developing a combination of two products to monitor snow water. Retrospective analysis for research and applications. Longterm changes in global, regional, and local snow depth h s, snow water equivalent swe, and extent will ultimately have major ramifications for ecosystem function, human utilization of snow. Both glaciers and snowpack form natural reservoirs that gradually release water during the drier summer months, providing drinking water and ecosystem services the varied benefits that organisms gain from the natural environment and. Basin boundary data sets and rfc boundaries are provided here in shapefiles that have been tarred and gzipped. Snotel stations are valuable, however, because they are the only reliable source of snow water equivalent data. Introduction knowledge of spatial snowpack properties in mountain regions, especially snow water equivalent swe, is critical for accurate assessment and forecasting of snowmelt timing. Community snow observation anthony arendt, university of washington, seattle. Review on remote sensing of the snow cover and on wmo. Remote sensing free fulltext highresolution reconstruction of.
National operational hydrologic remote sensing center nohrsc. So scientists are trying to pair these ground measurements with remote sensing to form a more comprehensive picture of mountain snowpack and its potential water supply. The objective of this study is to develop snow depth retrieval algorithm based on support vector regression svr technique using pm remote sensing data and other auxiliary data. Feasibility test of multifrequency radiometric data.
Synergistic use of remote sensing for snow cover and snow. Snow water equivalent swe snow modeling for fews net was developed and originally implemented by the noaa national operational hydrologic remote sensing center nohrsc, using a spatially distributed land surface model lsm operating within the land information system lis software framework version 6. Review of snow water equivalent microwave remote sensing. Estimating northern hemisphere snow water equivalent for. Estimating snow depth and snow water equivalence using. Estimates of the snow water equivalent swe the volume of fresh water that a given snowcovered area represents are required for water resource management, hydropower, and flood forecasting. Snow water equivalent swe is the amount of water contained in snowpack in the northern and southern hemispheres measured in millimeters mm. Snow water equivalent copernicus global land service.
The need is especially great in the remote arctic and sub arctic regions where snow is extremely important to the annual runoff, surface snow surveys are sparsely distributed and many basins have little or no data on snow. He is working in the field of microwave remote sensing and land based applications for more than 34 years. Remote sensing of snow cryosphere geophysics and remote sensing. In many ways, the research questions involving seasonal snow have not changed over the past several decades since the inception of remote sensing. Insar for estimation of changes in snow water equivalent of dry snow, ieee transactions on geoscience and remote. Beginning with the launch of nimbus7 satellite, the research on microwave snow water equivalent remote sensing has developed for more than 30 years, researchers have made progress in many aspects, including the electromagnetic scattering and emission modeling, ground and airborne experiments, and inversion algorithms for future global high. Swe measurements quantify the amount of water stored in sno. Evaluation of snodas snow depth and snow water equivalent estimates for the colorado rocky mountains, usa. Snodas is a modeling and data assimilation system developed by nohrsc to provide the best possible estimates of snow cover and associated parameters to support hydrologic modeling and analysis. Data are offered through the national snow and ice data center nsidc.
Usgs hydrologic technician jim caldwell uses an aluminum tube and scale to measure snow depth, snow water content and snow density as part of the maine cooperative snow survey. The application of remote sensing and a blowing snow model to. In the use of space borne remote sensing of snow cover it is desirable to obtain three main parameters. Snow in alpine regions is a lifesustaining part of the water cycle. Precipitation is a key hydrological and climate variable that includes both liquid rain and solid snow and ice forms. Estimating snow water equivalent for a slightly tilted snowcovered prairie grass field by gps interferometric reflectometry. Calculation of energy balance of a snow pack, estimation of snow properties snow grain. Snow depth sensors measure the depth of the snowpack. However, data is often lacking on the water content snow water equivalence swe, extent and depth of the seasonal snow cover. Estimating snow depth and snow water equivalence using repeat. Four noaa corps officers pilot the aircraft and operate the remote sensing systems. Our sensors are used at ski resorts to improve management of their resources. Amsreaqua daily l3 global snow water equivalent ease. National weather service national operational hydrologic remote sensing center office of water prediction 1735 lake drive w.
Multisource and multitemporal remote sensing data therefore hold great promise for moving the monitoring and analysis of snow toward estimates of a suite of snow properties at high spatial and temporal resolution. The nohrsc measures snow water equivalent and soil moisture using. Snow cover area sca, snow depth sd and snow water equivalent swe. Using the density of water, we can also report cloud liquid water as kgm2 1 mm, or gcm2 10 mm. National snow analyses nohrsc the ultimate source for. Snow data assimilation system snodas data products at nsidc. Dear colleagues, in recent years, remote sensing has become increasingly important in earth system science, and, especially, for the monitoring of the terrestrial water cycle with the launch of a great numbers of satellites, covering various applications rainfall, soil moisture, flood extent, surface water level, terrestrial water storage, snow and ice, floods. To provide highly accurate and reliable basinwide distributed measurements of snow water equivalent and forecasts of snowmelt runoff with unique remote sensing and physical modeling, allowing the global water community to make the best use of our planets water resources. Toward advanced daily cloudfree snow cover and snow water equivalent products from terraaqua modis and aqua amsre measurements. Evaluation of remotely sensed snow water equivalent and snow. These files do not contain the imagery itself, rather they point to data available online.
A citizen science campaign to validate snow remote sensing. The national operational hydrologic remote sensing center nohrsc provides remotelysensed and modeled hydrology products for the coterminous u. Snow data assimilation system snodas data from the national operational hydrologic remote sensing center nohrsc are processed daily to calculate snow water equivalent swe and snow coverage statistics for water supply basins in colorado. We still want to know the spatial extent of snow cover, snowpack properties such as grain size and albedo, snow depth, snow water equivalent. Snodas is a modeling and data assimilation system developed by nohrsc to provide the best possible estimates. Beginning with the launch of nimbus7 satellite, the research on microwave snow water equivalent remote sensing has developed for more than 30 years, researchers have made progress in many aspects. The physical properties of a snowpack strongly influence the emissions from the substratum, making snow property retrievals feasible by means of the surface brightness temperature observed by passive microwave sensors. Developing the tools needed to remotely measure snow water equivalent swe is a priority, as swe is currently sparsely sampled insitu, and there is no remote sensing product available for mountainous regions, while spatial swe estimates are required for current water resource management and climate studies. Ieee transactions on geoscience and remote sensing 35. Snow water equivalence swe represents the total amount of water available if the snowpack were melted instantaneously. Snow models are routinely used independently of remote sensing techniques to estimate swe.