Four noaa corps officers pilot the aircraft and operate the remote sensing systems. Remote sensing of snow depth and snow water equivalent remote. Software titles near real time snow remote sensing processing and analysis workflow for modis and amsr2. About snow water equivalent and snow depth sensors campbell scientific offers two types of sensors for snowpack applications. Remote sensing of snow cryosphere geophysics and remote. Estimating snow depth and snow water equivalence using. National operational hydrologic remote sensing center nohrsc. Basin areas were delineated using gis methods and a 1km digital elevation model. Amsreaqua daily l3 global snow water equivalent easegrids.
These files do not contain the imagery itself, rather they point to data available online. 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. Snow water equivalent anomaly for iraq, from famine early warning systems network fews net data portal details. By measuring the time between the pulse and its return echo, the distance between the. Station snow water equivalent reports station snowdepth reports. Insar for estimation of changes in snow water equivalent of dry snow, ieee transactions on geoscience and remote. 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. Support vector regression snowdepth retrieval algorithm. Snow data assimilation system snodas data products at nsidc. There is no remote sensing instrument to monitor snow water equivalent at useful spatial andor temporal resolutions in the hindu kush himalayan hkh region. Review on remote sensing of the snow cover and on wmo.
Accurately tracking the depth and water content of snow is critical. Review of snow water equivalent retrieval methods using. Evaluation of passive microwave snow water equivalent retrievals across the boreal forest tundra transition of western canada. Product version, access, sensor, temporal coverage, spatial information. Interpretation of ssmi measurements over greenland. 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. Synergistic use of remote sensing for snow cover and snow. Calculation of energy balance of a snow pack, estimation of snow properties snow grain. Snodas is a modeling and data assimilation system developed by nohrsc to provide the best possible estimates. Report dso201404 gridded snow water equivalent data set. Unfortunately, of the three snow metrics listed above, only extent. Precipitation is a key hydrological and climate variable that includes both liquid rain and solid snow and ice forms. Remote sensing of snow with passive microwave radiometers.
Snow depth sensors measure the depth of the snowpack. Snow water equivalent how is snow water equivalent abbreviated. Quantifying the relationships between lake fraction, snow. 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. 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.
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. 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. Using remote sensing to estimate snow depth and snow water. A citizen science campaign to validate snow remote sensing. This unique observing system includes two lowflying aircraft to conduct surveys in 31 states, including alaska, as well as in 8 canadian provinces. Evaluation of remotely sensed snow water equivalent and snow. National operational hydrologic remote sensing center the. Feasibility test of multifrequency radiometric data. 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. He is working in the field of microwave remote sensing and land based applications for more than 34 years.
Our sensors are used at ski resorts to improve management of their resources. Snow in alpine regions is a lifesustaining part of the water cycle. Spatial distribution of snow cover, surface albedo and snow water equivalent. Projects subzero research laboratory montana state university. Snow data assimilation system snodas data products at. May 07, 2020 snow cover is the presence of snow on land or bodies of water. Retrospective analysis for research and applications. This survey is conducted throughout maine in the spring to aid in the evaluation of flood potential by the maine river flow advisory commission. Amsreaqua daily l3 global snow water equivalent ease. The application of remote sensing and a blowing snow model to. National operational hydrologic remote sensing center.
The snow cover can be identified by applying a threshold to the spectral difference. 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. 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. 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. Currently, the accurate estimation of the maximum snow water equivalent swe in mountainous areas is an important topic. 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. 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. Estimating northern hemisphere snow water equivalent for.
Projects subzero research laboratory montana state. Training on remote sensing of snow water resources in the. The national operational hydrologic remote sensing center nohrsc has developed, and currently maintains, an operational airborne gamma radiation snow survey program to make airborne snow water equivalent swe and soil moisture measurements. Using the density of water, we can also report cloud liquid water as kgm2 1 mm, or gcm2 10 mm. Quantifying the uncertainty in passive microwave snow water equivalent observations. Snow water equivalence swe represents the total amount of water available if the snowpack were melted instantaneously. As the distance between the sensor and the snow surface decreases, the time it takes for the echo to return also decreases. 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. 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. 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. In the use of space borne remote sensing of snow cover it is desirable to obtain three main parameters. National weather service national operational hydrologic remote sensing center office of water prediction 1735 lake drive w.
Remote sensing of snow water equivalent has been a goal of hydrologists and atmospheric scientists for many years. 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. Ieee transactions on geoscience and remote sensing 35. The nohrsc produces snow products and information that include estimates of. Information about snow water equivalent is needed in applications such as flood. The national operational hydrologic remote sensing center nohrsc provides remotelysensed and modeled hydrology products for the coterminous u. Remote sensing data of snow coverare now wellsuited for use in hydrologic and generalcirculationmodels. Gis data sets nohrsc the ultimate source for snow information. National snow analyses nohrsc the ultimate source for. Evaluation of remotely sensed snow water equivalent and snow cover extent.
Thus, the large scale snow water equivalent information is mainly from remote sensing. The major characteristics of the snow cover are its height and snow water equivalent. 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. Sca is easily observable at optical visible and nearinfrared wavelengths because of the strong albedo contrast between snow covered and snowfree land.
Jonathan munoz 1, jose infante 1, tarendra lakhankar1, reza khanbilvardi 1, peter romanov 1, nir krakauer 1 and al powell 2. Snow water equivalent swe measurements are necessary for the management of water supply and flood control systems in seasonal snowcovered regions. Toward advanced daily cloudfree snow cover and snow water equivalent products from terraaqua modis and aqua amsre measurements. Airborne snow survey program nohrsc the ultimate source. 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. The snow sensor probe is mounted above a standard snow board. 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.
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. Swe measurements quantify the amount of water stored in sno. Snow water equivalent swe is the amount of water contained in snowpack in the northern and southern hemispheres measured in millimeters mm. Remote sensing free fulltext highresolution reconstruction of. 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. Evaluation of snodas snow depth and snow water equivalent estimates for the colorado rocky mountains, usa. Swe sensors measure the amount of water contained within a snowpack. 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. Each cell of the snow water equivalent grids with units of depth was multiplied by its area to obtain water volume estimates per grid cell. Rao is a professor at the centre of studies in resources engineering, indian institute of technology bombay, mumbai, india.
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. Units of measurement are mm, the depth of the liquid water in the vertical column. However, data is often lacking on the water content snow water equivalence swe, extent and depth of the seasonal snow cover. Data are offered through the national snow and ice data center nsidc. Estimating snow water equivalent for a slightly tilted snowcovered prairie grass field by gps interferometric reflectometry. Clicking on the link should open and load the imagery into the client application. 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. Snotel stations are valuable, however, because they are the only reliable source of snow water equivalent data. Download gridded national snow analyses data sets for geospatial applications. Sensor logics automated lowpower snow water equivalent sensor swedar can improve forecasting of water resources for agriculture and public consumption.
Passive microwave pm remote sensing data have long been used to retrieve snow depth and snow water equivalent with large uncertainties. Estimating snow depth and snow water equivalence using repeat. We still want to know the spatial extent of snow cover, snowpack properties such as grain size and albedo, snow depth, snow water equivalent. 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. 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. 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. Review of snow water equivalent microwave remote sensing. The nohrsc measures snow water equivalent and soil moisture using gamma radiation remote sensing. Over a billion people worldwide depend on snowmelt for water supply.
Snowcover reconstruction methodology for mountainous regions based on historic in situ observations and recent remote sensing data. Snow water equivalent swe is the most important parameter used to initialize snow cover in standalone hydrology models. Retrieval of water equivalent of snow cover in finland by satellite microwave radiometry. 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 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. Accurately tracking the depth and water content swe of snow is critical to monitoring the seasonal snow pack. 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. Snow cover area sca, snow depth sd and snow water equivalent swe. Fundamemtals of hyperspectral remote sensing gis resources.
Estimating snow water equivalent using snow depth data and. 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. Basin boundary data sets and rfc boundaries are provided here in shapefiles that have been tarred and gzipped. Introduction knowledge of spatial snowpack properties in mountain regions, especially snow water equivalent swe, is critical for accurate assessment and forecasting of snowmelt timing. 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.
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. Snow has a big impact on the climate, hydrological and soil processes, plant and animal life, human activity. The nohrsc measures snow water equivalent and soil moisture using. Community snow observation anthony arendt, university of washington, seattle. Snow water equivalent copernicus global land service. 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. Synergistic use of remote sensing for snow cover and snow water equivalent estimation. Snow models are routinely used independently of remote sensing techniques to estimate swe. Snow water equivalent is the estimate of the depth of liquid water contained within the snowpack.
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