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NASA NTRS1990

Satellite remote sensing of water resources in the Yangtze and Yellow Rivers of China based on infrared imagery of cloud distributions

Although the two largest rivers in China originate in the same region, separated only by the Bayanhar Mountains as a watershed, the Yangtze and Yellow Rivers behave in quite different ways. Most of the warm and humid air currents from the Arabian Sea and Bay of Bengal are blocked by the Bayanhar Mountains. As a result, the amount of water in the Yellow River is only 5 percent of that in the Yangtze River. Based on the cloud coverage area and the cloud volumetric distributions, and also the thickness above 9.4 kms of the cumulus clouds located north and south of the Bayanhar Mountains, from GEO satellite IR imagery, the results suggest that a more detailed investigation is warranted in the hope that the proper modification of cumuli north of the Bayanhar Mountains would enhance the rainfall over the fountainhead of the Yellow River.

Hung, R. J.↗

NASA NTRS1992

The impact of global warming on river runoff

A global atmospheric model is used to calculate the annual river runoff for 33 of the world's major rivers for the present climate and for a doubled CO2 climate. The model has a horizontal resolution of 4 x 5 deg, but the runoff from each model grid box is quartered and added to the appropriate river drainage basin on a 2 x 2.5 deg resolution. The computed runoff depends on the model's precipitation, evapotranspiration, and soil moisture storage. For the doubled CO2 climate, the runoff increased for 25 of the 33 rivers, and in most cases the increases coincide with increased rainfall within the drainage basins. There were runoff increases in all rivers in high northern latitudes, with a maximum increase of 47 percent. At low latitudes there were both increases and decreases ranging from a 96 increase to a 43 percent decrease. The effect of the simplified model assumptions of land-atmosphere interactions on the results is discussed.

Miller, James R.↗

NASA NTRS1995

Mineralogic variations in fluvial sediments contaminated by mine tailings as determined from AVIRIS data, Coeur D'Alene River Valley, Idaho

The success of imaging spectrometry in mineralogic mapping of natural terrains indicates that the technology can also be used to assess the environmental impact of human activities in certain instances. Specifically, this paper describes an investigation into the use of data from the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS) for mapping the spread of, and assessing changes in, the mineralogic character of tailings from a major silver and base metal mining district. The area under investigation is the Coeur d'Alene River Valley in northern Idaho. Mining has been going on in and around the towns of Kellogg and Wallace, Idaho since the 1880's. In the Kellogg-Smelterville Flats area, west of Kellogg, mine tailings were piled alongside the South Fork of the Coeur d'Alene River. Until the construction of tailings ponds in 1968 much of these waste materials were washed directly into the South Fork. The Kellogg-Smelterville area was declared an Environmental Protection Agency (EPA) Superfund site in 1983 and remediation efforts are currently underway. Recent studies have demonstrated that sediments in the Coeur d'Alene River and in the northern part of Lake Coeur d'Alene, into which the river flows, are highly enriched in Ag, Cu, Pb, Zn, Cd, Hg, As, and Sb. These trace metals have become aggregated in iron oxide and oxyhydroxide minerals and/or mineraloids. Reflectance spectra of iron-rich tailing materials are shown. Also shown are spectra of hematite and goethite. The broad bandwidth and long band center (near 1 micron) of the Fe(3+) crystal-field band of the iron-rich sediment samples combined with the lack of features on the Fe(3+) -O(2-) charge transfer absorption edge indicates that the ferric oxide and/or oxyhydroxide in these sediments is poorly crystalline to amorphous in character. Similar features are seen in poorly crystalline basaltic weathering products (e.g., palagonites). The problem of mapping and analyzing the downriver occurrences of iron rich tailings in the Coeur d'Alene (CDA) River Valley using remotely sensed data is complicated by the full vegetation cover present in the area. Because exposures of rock and soil were sparse, the data processing techniques used in this study were sensitive to detecting materials at subpixel scales. The methods used included spectral mixture analysis and a constrained energy minimization technique.

Farrand, W. H.↗

NASA NTRS1994

Interpretation of the coastal zone color scanner signature of the Orinoco River plume

The Caribbean Sea is an area that traditionally has been considered oligotrophic, even though the Orinoco River contributes large quantities of fresh water, nutrients, and other dissolved material to this region during the wet boreal (fall) season. Little is known about the impact of this seasonal river plume, which extends from Venezuela to Puetro Rico shortly after maximum discharge. Here, we present results from a study of the bio-optical characteristics of the Orinoco River plume during the rainy season. The objective was to determine whether the coastal zone color scanner (CZCS) and the follow-on sea-viewing wide-field-of-view sensor (SeaWiFS) satellite instrument can be used to assess the concentrations of substances in large river plumes. Recent in situ shipboard measurements were compared to values from representative historical CZCS images using established bio-optical models. Our goal was to deconvolve the signatures of colored dissolved organic carbon and phytoplankton pigments within satellite images of the Orinoco River plume. We conclude that the models may be used for case 2 waters and that as much as 50 percent of the remotely sensored chlorophyll biomass within the plume is an artifact due to the presence of dissolved organic carbon. Dissolved organic carbon originates from a number of sources, including decay of dead organisms, humic materials from the soil, and gelbstoff.

Hochman, Herschel T.↗

NASA NTRS2002

Airborne Microwave Imaging of River Velocities

The objective of this project was to determine whether airborne microwave remote sensing systems can measure river surface currents with sufficient accuracy to make them prospective instruments with which to monitor river flow from space. The approach was to fly a coherent airborne microwave Doppler radar, developed by APL/UW, on a light airplane along several rivers in western Washington state over an extended period of time. The fundamental quantity obtained by this system to measure river currents is the mean offset of the Doppler spectrum. Since this scatter can be obtained from interferometric synthetic aperture radars (INSARs), which can be flown in space, this project provided a cost effective means for determining the suitability of spaceborne INSAR for measuring river flow.

Plant, William J.↗

NASA NTRS1999

Review of historical monitoring data on Techa River contamination

The Mayak Production Association was the first Russian site for the production and separation of plutonium. The extensive increase in plutonium production during 1948-1955, as well as the absence of reliable waste-management technology, resulted in significant releases of liquid radioactive effluent into the rather small Techa River. This resulted in chronic external and internal exposure of about 30,000 residents of riverside communities; these residents form the cohort of an epidemiologic investigation. Analysis of the available historical monitoring data indicates that the following reliable data sets can be used for reconstruction of doses received during the early periods of operation of the Mayak Production Association: Temporal pattern of specific beta activity of river water for several sites in the upper Techa region since July 1951; average annual values of specific beta activity of river water and bottom sediments as a function of downstream distance for the whole river since 1951; external gamma-exposure rates near the shoreline as a function of downstream distance for the whole Techa River since 1952; and external gamma-exposure rate as a function of distance from the shoreline for several sites in the upper and middle Techa since 1951.

NASA Discipline Radiation Health↗

NASA NTRS2012

The Surface Water and Ocean Topography Satellite Mission - An Assessment of Swath Altimetry Measurements of River Hydrodynamics

The Surface Water and Ocean Topography (SWOT) satellite mission, scheduled for launch in 2020 with development commencing in 2015, will provide a step-change improvement in the measurement of terrestrial surface water storage and dynamics. In particular, it will provide the first, routine two-dimensional measurements of water surface elevations, which will allow for the estimation of river and floodplain flows via the water surface slope. In this paper, we characterize the measurements which may be obtained from SWOT and illustrate how they may be used to derive estimates of river discharge. In particular, we show (i) the spatia-temporal sampling scheme of SWOT, (ii) the errors which maybe expected in swath altimetry measurements of the terrestrial surface water, and (iii) the impacts such errors may have on estimates of water surface slope and river discharge, We illustrate this through a "virtual mission" study for a approximately 300 km reach of the central Amazon river, using a hydraulic model to provide water surface elevations according to the SWOT spatia-temporal sampling scheme (orbit with 78 degree inclination, 22 day repeat and 140 km swath width) to which errors were added based on a two-dimension height error spectrum derived from the SWOT design requirements. Water surface elevation measurements for the Amazon mainstem as may be observed by SWOT were thereby obtained. Using these measurements, estimates of river slope and discharge were derived and compared to those which may be obtained without error, and those obtained directly from the hydraulic model. It was found that discharge can be reproduced highly accurately from the water height, without knowledge of the detailed channel bathymetry using a modified Manning's equation, if friction, depth, width and slope are known. Increasing reach length was found to be an effective method to reduce systematic height error in SWOT measurements.

Wilson, Matthew D.↗

NASA NTRS2019

Performance of Landsat-8 and Sentinel-2 Surface Reflectance Products for River Remote Sensing Retrievals of Chlorophyll-A and Turbidity

Rivers and other freshwater systems play a crucial role in ecosystems, industry, transportation and agriculture. Despite the more than 40 years of inland water observations made possible by optical remote sensing, a standardized reflectance product for inland waters is yet forthcoming. The aim of this work is to compare the standard USGS land surface reflectance product to two Landsat-8 and Sentinel-2 aquatic remote sensing reflectance products over the Amazon, Columbia and Mississippi rivers. Landsat-8 reflectance products from all three routines are then evaluated for their comparative performance in retrieving chlorophyll-a and turbidity in reference to shipborne, underway in situ validation measurements. The land surface product shows the best agreement (4 percent Mean Absolute Percent Difference) with field measurements of radiometry collected on the Amazon River and generates 36 percent higher reflectance values in the visible bands compared to aquatic methods (ACOLITE (Atmospheric Correction for OLI (Operational Land Imager) 'lite') and SeaDAS (Sea-viewing Wide Field-of-View Sensor (SeaWiFS) Data Analysis System)) with larger differences between land and aquatic products observed in Sentinel-2 (0.01 per steraradian) compared to Landsat-8 (0.001 per steraradian). Choice of atmospheric correction routine can bias Landsat-8 retrievals of chlorophyll-a and turbidity by as much as 59 percent and 35 percent respectively. Using a more restrictive time window for matching in situ and satellite imagery can reduce differences by 5–31 percent depending on correction technique. This work highlights the challenges of satellite retrievals over rivers and underscores the need for future optical and biogeochemical research aimed at improving our understanding of the absorbing and scattering properties of river water and their relationships to remote sensing reflectance.

Landsat-8↗

NASA NTRS2021

Preferential Loss of Yukon River Delta Colored Dissolved Organic Matter under Nutrient Replete Conditions

The Yukon River exports a large amount of dissolved organic carbon (DOC), much of which is colored, absorbing visible and ultraviolet light. Yukon River water typically has low total dissolved nitrogen (TDN), with an average DOC : TDN ratio of 21.1 (mol C mol N−1) ~ 200 km upstream from the coast at Pilot Station, Alaska. TDN has been correlated to the bioavailability of DOC, but a direct estimate of the dependence of DOC reactivity on nutrient availability has not been conducted in the Yukon River delta. The biodegradability of DOC and colored dissolved organic matter (CDOM) was assessed along a gradient within the Yukon River delta and into the coastal ocean. Samples were dark incubated at 20􀀀C and half of the incubations were amended with inorganic nutrients. At ﬁve time points through 27 d, CDOM absorption and DOC concentration were measured. Initial DOC concentration was 113–830 μmol C L−1 and CDOM absorption at 443 nm (a443) ranged from 0.16 to 7.8 m−1 from the ocean to a high CDOM lake. DOC was relatively unreactive, with 3–6% of DOC degrading in riverine samples and little difference between nutrient amended and control incubations. Control river delta a443 decreased 3–10%, while nutrient amended treatments saw a 6–22% decline over 27 d. In the nutrient amended riverine stations, CDOM absorption loss was greater at blue wavelengths and CDOM degradation was greater than total DOC loss. DOC was resistant to biodegradation in both nutrient amended and ambient conditions, while CDOM was preferentially degraded when nutrients were replete.

J Blake Clark↗

NASA NTRSDate not supplied

Medium-Range River Flood Forecasts Using a Long Short-Term Memory Network

River flooding and the impacts are a concern for decision makers throughout the United States. Accurate medium-range forecasts (~3-7 days) are critical for providing advanced outlooks to emergency management officials. Unfortunately, accurately forecasting rainfall-runoff and the subsequent rise and fall within rivers remain a challenge in hydrological modeling. While complex physical modeling systems are the standard for representing the hydrological processes, they are computationally demanding and can require extensive calibration. Further, uncertainties remain in the model parameters and input data. The use of machine learning can reduce some of the computational demand while maintaining high accuracy. Therefore, this project makes use of a Long Short-Term Memory (LSTM) network which explicitly accounts for the time-dependent nature of rainfall-runoff modeling. The developed LSTM was trained to predict river gauge height, or stage height, based on time-lagged input features which include: gauge height to initialize the model, the NASA Short-term Prediction Research and Transition Center’s instance of the Land Information System (SPoRT-LIS) relative soil moisture to describe the rainfall infiltration rate, and 6-hr Multi-Radar Multi-Sensor quantitative precipitation estimate (MRMS QPE). The developed LSTM based system is then used to produce 7-day forecasts with a 6-hr temporal resolution using three different quantitative precipitation forecasts (QPF) from the NWS’s Weather Prediction Center (WPC), the NCEP Global Forecast System (GFS) model and the National Blend of Models (NBM). This trained modeling system has been implemented as an experimental product at over 100 different rivers in collaboration with at multiple National Weather Service (NWS) Forecast Offices and River Forecast Centers (RFC) across the eastern half of the United States. The developed LSTM model achieved average Nash-Sutcliffe efficiency (NSE) 0.89 higher than the equivalent medium-range National Water Model ensemble member forecast over a 7-day forecast. In addition to the initial development and evaluation, this project has continued to expand. While the initial model was developed for precipitation dominated basins, expansion of the project has taken it to basins effected by snow melt. This presentation will provide an overview of the project with focus on recent developments on incorporating snow melt processes into the model.

Andrew T. White↗

NASA NTRS2023

Explainable deep learning for insights in El Niño and river flows

The El Niño Southern Oscillation (ENSO) is a semi-periodic fluctuation in sea surface temperature (SST) over the tropical central and eastern Pacific Ocean that influences interannual variability in regional hydrology across the world through long-range dependence or teleconnections. Recent research has demonstrated the value of Deep Learning (DL) methods for improving ENSO prediction as well as Complex Networks (CN) for understanding teleconnections. However, gaps in predictive understanding of ENSO-driven river flows include the black box nature of DL, the use of simple ENSO indices to describe a complex phenomenon and translating DL-based ENSO predictions to river flow predictions. Here we show that eXplainable DL (XDL) methods, based on saliency maps, can extract interpretable predictive information contained in global SST and discover SST information regions and dependence structures relevant for river flows which, in tandem with climate network constructions, enable improved predictive understanding. Our results reveal additional information content in global SST beyond ENSO indices, develop understanding of how SSTs influence river flows, and generate improved river flow prediction, including uncertainty estimation. Observations, reanalysis data, and earth system model simulations are used to demonstrate the value of the XDL-CN based methods for future interannual and decadal scale climate projections.

SST↗

NASA NTRSDate not supplied

Assessing the Feasibility of Using Various Earth Observations to Monitor Environmental Trends Associated with River Flow Impediments Near Energy Intake Structures

Grassing events, characterized by the release of river vegetation in large quantities, are often responsible for major flow impediments surrounding industrial water intake structures. These sudden flow impediments halt critical municipal functions, such as cooling at energy generating facilities, leading to widespread energy disruptions for surrounding communities. Because the origin and cause of grassing events in rivers are largely unknown, employees at these facilities can only reactively respond after they occur by pausing energy generation to manually remove the accumulation of aquatic vegetation. In 2023, the Dresden Generating Station, in collaboration with the United States Geological Survey, began looking into using remote sensing methodologies to locate floating aquatic vegetation surrounding their intake structure located along the Kankakee River in northern Illinois. This project contributed to this effort by conducting a case study that compared the performance, practicality, and feasibility of using various Earth observations (Landsat 9 OLI-2, Landsat 8 OLI, Sentinel-2 MSI, and DOVE PlanetScope) and vegetation indices (NDVI, EVI, SAVI, and GCI) to monitor aquatic vegetation in the Kankakee River. Additionally, this study incorporated several environmental metrics to identify potential triggers for grassing events. Results from this project found that while Landsat sensors provide a lower spatial resolution than commercial satellite Earth observations, areas of aquatic vegetation were similarly identified; therefore, it may not be necessary to acquire expensive, high-resolution datasets for continued monitoring. Finally, preliminary correlation analyses showed a potential negative relationship between the river discharge and the presence of aquatic vegetation (-0.875 correlation coefficient), suggesting that periods of low flow could lead to large releases in aquatic vegetation.

Marisa Smedsrud↗

NASA NTRS1973

Break-up characteristics of Chena River Basin

The author has identified the following significant results. While visually analyzing ERTS-1 data for August and September, 1972, it was found that lakes as small as 200 feet in diameter were visible on the imagery. An examination of the imagery for the Minto Lakes area shows that the lakes take on their darkest appearance in MSS band 6. The Tanana River which flows through this area appears quite light in band 5, quite dark in band 7, and is almost undetectable for band 6. The significance of these data are that potential surface storage could be measured for watersheds that have substantial numbers of lakes. This potential storage would be available to both spring runoff and summer precipitation. Caution must be shown because certain clouds cast a shadow that is similar to the lake appearance. The difference of the imagery for a lake and a river of the same band is due to the sediment load for the river. The Tanana River had a heavy glacial sediment load. The area of snow cover during the fall accumulation can be mapped in detail.

Carlson, R. F.↗

NASA NTRS1973

Monitoring of streamflow in the Verde River by ERTS-1 Data Collection System (DCS)

The Verde River watershed in central Arizona furnishes municipal, industrial, and agricultural water to the Salt River Valley --an area that contains more than half of Arizona's population and about one-fourth of the State's irrigated land. Water-management decisions related to the operation of large multiple-use reservoirs require accurate and continuous monitoring of moisture conditions over large remote areas. The U.S. Geological Survey in cooperation with the Salt River Valley Water Users' Association installed a specially designed gaging station on the Verde River near the town of Camp Verde to evaluate near-real time streamflow data furnished by the ERTS-1 Data Collection System (DCS). On Nov. 3, 1972, the installation was equipped with a Stevens digital water-level recorder, modified for telemetry, and an ERTS-1 data collection platform operating in the digital-parallel mode.

Schumann, H. H.↗

NASA NTRS1977

Volcanism of the Eastern Snake River Plain, Idaho: A comparative planetary geology-guidebook

The Planetary Geology Field Conference on the central Snake River Plain was conceived and developed to accomplish several objectives. Primarily, field conferences are sponsored by the National Aeronautics and Space Administration to draw attention to aspects of terrestrial geology that appear to be important in interpreting the origin and evolution of extraterrestrial planetary surfaces. Another aspect is to present results of recent research in a region. A final objective of this conference is to bring together investigators of diverse backgrounds who share a common interest in the Snake River Plain. The Snake River Plain appears to be similar in surface morphology to many volcanic regions on the Moon, Mars, and possibly Mercury. Therefore, the Snake River Plain, in combination with the relatively good state of preservation, the lack of forests or other heavy vegetation, and the good network of jeep trails, is an area nearly ideal for analog studies.

Greeley, R.↗

NASA NTRS1978

Aerial photographic water color variations from pollution in the James River

A photographic flight was made over the James River on May 17, 1977. The data show that, in general, James River water has very high sunlight reflectance. In the Bailey Bay area this reflectance is drastically reduced. Also shown is a technique for normalizing off-axis variations in radiance film exposure from camera falloff and uneven sunlight conditions to the nadir value. After data normalization, a spectral analysis is performed that identifies Bailey Creek water in James River water. The spectral results when compared with laboratory spectrometer data indicate that reflectance from James River water is dominated by suspended matter, while the substance most likely responsible for reduced reflectance in Bailey Creek water is dissolved organic carbon.

Bressette, W. E.↗

NASA NTRS1986

Influence of the Yukon River on the Bering Sea

The relationships between the discharge of the Yukon River to the currents and biological productivity in the northern Bering Sea were studied. Specific objectives were: to develop thermal, sediment, and chlorophyll surface maps using Thematic Mapper (TM) data of the discharge of the Yukon River and the Alaskan Coastal Current during the ice free season; to develop a historical model of the distribution of the Yukon River discharge and the Alaskan Coastal Current using LANDSAT Multispectral band scanner (MSS) and NOAA satellite imagery; and to use high resolution TM data to define the surface dynamics of the front between the Alaskan Coastal Current and the Bering Shelf/Anadyr Current. LANDSAT MSS, TM, and Advanced Very High Resolution Radiometer (AVHRR) data were recorded during the 1985 ice free period. The data coincided with shipboard measurements acquired by Inner Shelf Transfer and Recycling (ISTAR) project scientists. An integrated model of the distribution of turbid water discharged from the Yukon River was compiled. A similar model is also being compiled for the Alaskan Coastal and Bering Shelf/Anadyr water masses based on their thermal expressions seen on AVHRR imagery.

Dean, K.↗

NASA NTRS1986

Paleodrainages of the Eastern Sahara - The radar rivers revisited (SIR-A/B implications for a mid-tertiary Trans-African drainage system)

The images obtained by the Shuttle Imaging Radar (SIR)-A and -B systems over the southwestern Egypt and northwestern Sudan were coregistered with the Landsat images and the existing maps to aid in extrapolations of the buried paleodrainages ('radar rivers'), first discovered by SIR-A. Field observations explain the radar responses of three types of radar rivers, RR-1 (broad, aggraded valleys filled with alluvium), RR-2 (braided channels inset in the RR-1 valleys), and RR-3 (narrow, long, bedrock-incised channels). A generalized model of the radar rivers, based on field studies and regional geologic relations, shows inferred changes in river regimen since the large valleys were established during the later Paleogene-early Neogene. It is suggested that a former Trans-African master stream system may have flowed from headwaters in the Red Sea Hills southwestward across North Africa, discharging into the Atlantic at the Paleo-Niger delta, prior to the Neogene domal uplifts and building of volcanic edifices across the paths of these ancient watercourses.

Mccauley, J. F.↗