The United States has an average elevation of roughly 2,500 feet (763m) above sea level, however there is a stark contrast in elevations across the country. Highest states Colorado is the highest state in the United States, with an average elevation of 6,800 feet (2,074m) above sea level. The 10 states with the highest average elevation are all in the western region of the country, as this is, by far, the most mountainous region in the country. The largest mountain ranges in the contiguous western states are the Rocky Mountains, Sierra Nevada, and Cascade Range, while the Appalachian Mountains is the longest range in the east - however, the highest point in the U.S. is Denali (Mount McKinley), found in Alaska. Lowest states At just 60 feet above sea level, Delaware is the state with the lowest elevation. Delaware is the second smallest state, behind Rhode Island, and is located on the east coast. Larger states with relatively low elevations are found in the southern region of the country - both Florida and Louisiana have an average elevation of just 100 feet (31m) above sea level, and large sections of these states are extremely vulnerable to flooding and rising sea levels, as well as intermittent tropical storms.

1:250000 scale Digital Elevation Model of Arizona. Digital Elevation Model (DEM) is the terminology adopted by the USGS to describe terrain elevation data sets in a digital raster form. The standard DEM consists of a regular array of elevations cast on a designated coordinate projection system. The DEM data are stored as a series of profiles in which the spacing of the elevations along and between each profile is in regular whole number intervals. The normal orientation of data is by columns and rows. Each column contains a series of elevations ordered from south to north with the order of the columns from west to east. The DEM is formatted as one ASCII header record (A-record), followed by a series of profile records (B-records) each of which include a short B-record header followed by a series of ASCII integer elevations per each profile. The last physical record of the DEM is an accuracy record (C-record). A 30-minute DEM (2- by 2-arc second data spacing) consists of four 15-by 15-minute DEM blocks. Two 30-minute DEM's provide the same coverage as a standard USGS 30- by 60-minute quadrangle. Saleable units are 30- by 30-minute blocks, that is, four 15- by 15-minute DEM's representing one half of a 1:100,000-scale map.

Lake Mead's water elevation at the end of April 2025 was ******* feet above sea level, a small decrease in comparison to the previous month. In July 2022, the reservoir reached the lowest monthly water level recorded since Lake Mead was first formed by the Hoover Dam in the 1930s. At full capacity, Lake Mead has a water level of 1,229 feet above sea level. Lake Mead nearing dead pool status Situated on the border of Arizona and Nevada, Lake Mead is the largest reservoir in the United States. It is a crucial water source that provides drinking water to tens of millions of people in the states of Arizona, California, and Nevada. However, experts have warned that if the lake continues to recede due to the severe droughts across the Southwestern United States, it will become a dead pool. This means that there will not be enough water for the Hoover Dam to produce hydropower or deliver water downstream to metropolitan centers. U.S. water resources are depleting With large swathes of western U.S. recently suffering from a megadrought, which is a period of prolonged drought that spans more than two decades, many other lakes have been severely depleted in recent years. Water levels of major reservoirs in California have fallen to all-time lows in recent years. California’s two largest reservoirs, Shasta Lake and Oroville Lake, were at less than half capacity in July 2022. However, in spring 2023 they were both mostly replenished due to more favorable environmental factors.

To support the modeling of the Colorado River water storage area capacity tables by the U.S. Geological Survey (USGS) Utah Water Science Center in the Glen Canyon National Recreation Area in Utah and Arizona, the USGS Earth Resources Observation and Science (EROS) Center has created an integrated 1-meter topobathymetric digital elevation model (TBDEM) for Lake Powell, the second largest man-made reservoir in the United States. Located in south-central Utah and north-central Arizona, Lake Powell is a reservoir on the Colorado River created by the flooding of a natural canyon by the construction of Glen Canyon Dam. The new Lake Powell TBDEM consists of the best available multi-source topographic and bathymetric elevation data for Lake Powell onshore and offshore areas. The Lake Powell TBDEM integrates three different data sources including topographic light detection and ranging (lidar) point cloud data, multibeam bathymetric surveys, and historic topographic surveys obtained from the Department of the Interior (DOI) Bureau of Reclamation (BOR) and USGS Woods Hole Coastal Marine Science Center. The topographic, bathymetric, and historic topographic surveys were sorted and prioritized based on survey date, accuracy, spatial distribution, and point density to develop a TBDEM model based on the best available elevation data. The Lake Powell TBDEM spatial resolution is 1-meter with the general location ranging from Glen Canyon Dam northwest of Page, Arizona to White Canyon, Utah with elevations from 948.28 meters to 1440.94 meters referenced to North American Vertical Datum of 1988 (NAVD88), National Geodetic Survey Geoid 12B. The topographic lidar survey was acquired from 4/2/18 to 4/3/18. The bathymetry survey was acquired from 10/8/17 to 11/15/17. The historic topographic surveys ranged from 1947-1959. Some of the nearshore void zone (not covered by lidar or multibeam) was filled with historic topographic surveys digitized from historical maps from 1947-1959 and a kriging interpolation as published by the USGS Coastal National Elevation Database (CoNED) Applications Project at https://doi.org/10.2112/SI76-008. Additional information regarding the CoNED Applications Project is located at https://www.usgs.gov/land-resources/eros/coned.

This data set consists of a set of 136 ESRI formatted GRID data sets representing elevations in meters for the state of Arizona. Each file covers a half degree block and as a collection they cover the entire State of Arizona. The data were created by processing U.S.Geological Survey 30 meter Digital Elevation Model files for all of the 7.5 minute quadrangle map areas in Arizona. The processing produced ESRI formatted lattices (GRIDs) for each quadrangle. These were then merged into the half degree blocks.

This dataset has been created to meet the needs of the research community of Arizona State University. Apart from purely vizualization purposes (i.e. displaying the data on various maps) it can potentially be used for spatial modeling. The data consist of engineering-quality contours, also known as isolines, created from the NED 10-meter Digital Elevation Model subset to the extent somewhat exceeding Cetral Arizona - Phoenix LTER. Contours ( lines connecting points of equal height above sea level) are drawn at 15 meter intervals with the base set at 145 m of elevation. Contours are an exact interpretation of the grid surface model and may sometimes appear blocky looking, may cross, appear to intersect, or form an unclosed branching line. All these are valid engineering-quality interpretations of the elevation surface that cartographers typically modify (smooth) for aesthetic purposes.

Development of a high-resolution digital elevation model (DEM) of the pre-Glen Canyon Dam topography in Glen Canyon National Recreation Area, Utah and Arizona was initiated to assist the U.S. Geological Survey (USGS) in its Lake Powell coring program in the fall of 2018 (https://www.usgs.gov/centers/ut-water/science/lake-powell-coring). Topographic surveys of Glen Canyon were commissioned by the Bureau of Reclamation during the planning stages for Lake Powell as part of the Colorado River Storage Project (S. 500, 1956). The Colorado River arm was surveyed by Alster and Associates, Inc. in 1958 and 1959 at a contour interval of 10-feet from the river surface at the future dam site through where the 3,750-foot contour crosses the channel (above Hite, UT). The San Juan River arm was surveyed by Fairchild Aerial Surveys, Inc. in 1947 at a contour interval of 20-feet from the confluence between the San Juan and Colorado Rivers through where the 4,100-foot contour crosses the channel (east of Mexican Hat, UT), though this DEM only includes topography up to 3,800 feet. Digitization of these contour maps into vector data was finalized in 2019 by the USGS Utah Water Science Center. The National Park Service, Glen Canyon National Recreation Area and the Bureau of Reclamation, and Glen Canyon Environmental Studies contributed in the digitization (c. 1999). The hydrologically corrected, 2-meter DEM was developed with the Topo to Raster tool in ArcMap (v. 10.6.1). These data are provided as-is and may be subject to revisions without warrant or consent.

This dataset is from a precipitation manipulation experiment conducted at five grassland sites along an elevation gradient near Flagstaff, AZ. The data consist of pre- (1991 - 2015) and post-experimental (2016) treatment plant production and precipitation measurements. The plant production measurements were taken from satellite and hand-held spectroradiometer, in addition to plot-based harvests at the end of growing season.

These topographic/bathymetric digital elevation models (DEMs) were collected and compiled to characterize erosion and deposition in the Colorado River and in an adjacent zone of laterally recirculating flow (eddy) during both average flow conditions and during a controlled flood that occurred in March 2008. The objectives of the study were to measure changes sandbar morphology that occurred during changes in discharge associated with the controlled flood. These data were collected between February 6 and March 31, 2008 in a 1-mile study reach on the Colorado River within Grand Canyon National Park beginning 44.5 miles downstream from Lees Ferry, Arizona. These data were collected by the USGS Grand Canyon Monitoring and Research Center with cooperators from Northern Arizona University and funding provided by the Glen Canyon Dam Adaptive Management Program. All bathymetric data were collected with a multibeam sonar system (Reson Seabat 8124 sonar with TSS MAHRSS reference system for heave, pitch, roll, and heading). Topographic data were collected by conventional total station. These data can be used to study changes in channel morphology associated with changes in streamflow conditions.

This data set is a hill shade, of the 1:250000 scale Digital Elevation Model of Arizona. Digital Elevation Model (DEM) is the terminology adopted by the USGS to describe terrain elevation data sets in a digital raster form. The standard DEM consists of a regular array of elevations cast on a designated coordinate projection system. The DEM data are stored as a series of profiles in which the spacing of the elevations along and between each profile is in regular whole number intervals. The normal orientation of data is by columns and rows. Each column contains a series of elevations ordered from south to north with the order of the columns from west to east. The DEM is formatted as one ASCII header record (A-record), followed by a series of profile records (B-records) each of which include a short B-record header followed by a series of ASCII integer elevations per each profile. The last physical record of the DEM is an accuracy record (C-record). A 30-minute DEM (2- by 2-arc second data spacing) consists of four 15-by 15-minute DEM blocks. Two 30-minute DEM's provide the same coverage as a standard USGS 30- by 60-minute quadrangle. Saleable units are 30- by 30-minute blocks, that is, four 15- by 15-minute DEM's representing one half of a 1:100,000-scale map.

Product: Processed, classified lidar point cloud data tiles in LAS 1.4 format. Geographic Extent: Approximately 10,547 square miles across 11 AOIs in California and Arizona. Dataset Description: The CA-AZ FEMA R9 Lidar 2017 D18 lidar project called for the planning, acquisition, processing, and production of derivative products of lidar data to be collected at a nominal pulse sp...

This dataset represents 50 foot contour intervals for Arizona's counties. Datasets are also available for 100', 250', and 500' intervals. Each file covers an Arizona county or part of a county and as a collection covers the entire state. The data were created by processing hillshade TIF files derived from the U.S. Geological Survey National Elevation Dataset. The processing produced ESRI formatted coverages for each county or part of a county. The U.S. Geological Survey has developed a National Elevation Dataset (NED). The NED is a seamless mosaic of best-available elevation data. The 7.5-minute elevation data for the conterminous United States are the primary initial source data. In addition to the availability of complete 7.5-minute data, efficient processing methods were developed to filter production artifacts in the existing data, convert to the NAD83 datum, edge-match, and fill slivers of missing data at quadrangle seams. One of the effects of the NED processing steps is a much-improved base of elevation data for calculating slope and hydrologic derivatives. The specifications for the NED 1 arc second and 1/3 arc second data are - Geographic coordinate system, Horizontal datum of NAD83, except for AK which is NAD27, Vertical datum of NAVD88, except for AK which is NAVD29, Z units of meters.

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The question was to what degree are summer minimum temperature climate trends in the latter half of the 20th and early part of the 21st century attributed to local urban development as opposed to global climate change? The approach was to select a range of towns/cities in CA, NV, and AZ for which a pairing of sites from a town/city and a site outside that town/city was possible. Climate records for the period 1948 to 2007 were accessed, and statistical time trends determined for the urban vs. rural locations for towns/cities over a considerable range of population (i.e., from 3.5K to 3.2M). The urban heat island effect increased with the natural log of the population, ranging from a total change in minimum monthly temperatures of ca. 1.5F to over 12F over the population range of 3.5K to 3.2M. These rates of change in the 1948-2007 period overwhelm any background global climate change, with the exception of the rural sites and smaller towns. This study for the first time identified the temperature trends of a range of towns and cities in the Sonoran and Mojave deserts to unravel the impact of urban warming from that of global warming in the contemporary global warming era sometimes called the Anthropocene era. Previous literature investigatin these sites were only up to 1984 or did not address the urban warming contribution. The impact depends on land cover and extent of population development over time.

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An extensive precipitation database at the 149 km2 Walnut Gulch Experimental Watershed (WGEW) has been developed over the past 53 years with the first records starting in August 1953 and continuing to the present. The WGEW is a tributary of the San Pedro River, surrounds the town of Tombstone in southeastern Arizona, and has a drainage area of approximately 149 km2. Elevation of the watershed ranges from 1220 m to 1950 m above mean sea level (MSL). Average annual precipitation for the period of 1956-2005, as measured with six gauges, is roughly 312 mm, with approximately 60% falling during the summer monsoon. Precipitation consists almost solely of rainfall with relatively rare instances of hail and snowfall. From a historical high of 95 rain gauges, a current network of 88 gauges is operational. This constitutes one of the densest rain gauge networks in the world (0.6 gauges/km2) for watersheds greater than 10 km2. Through 1999, the network consisted of analog recording weighing rain gauges. In 2000, a newly designed digital gauge with telemetry was placed adjacent (1 m) to the analog gauges. Both the analog and digital networks of gauges were in operation from 2000 to 2005 to enable a comparative analysis of the two systems. The analog data were digitized from paper charts and were stored in breakpoint format. The digital data consist of rainfall depths at 1-min intervals during periods of rainfall. Resources in this dataset:Resource Title: GeoData catalog record. File Name: Web Page, url: https://geodata.nal.usda.gov/geonetwork/srv/eng/catalog.search#/metadata/WalnutPrecipitation_jjm_2015-03-20_1018

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This dataset contains daily observations of several Parameters from all five C. Hart Merriam Elevation Gradient stations. All of the data is available online in a MySQL database which can be accessed from a webpage (http://cpbc.bio.nau.edu/gradient_weather_data/default.aspx) or by direct connection (contact Paul.Heinrich@nau.edu for access. The following parameters are recorded for each site: precipitation, air temperature, releative humidity, solar radiation, soil temperature at 3 depths, soil moisture at 2 or 3 depths depending on the site, wind speed and wind direction.

Elevation in the western United States obtained from the National Elevation Dataset. Data was converted from float point to integer format and resampled from 30m resolution to 90m resolution.

fp_bfe displays the flood hazard elevation contours that indicate the water surface elevation resulting from a flood that has a 1% chance of equaling or exceeding that level in any given year (100-year flood). See more information.This layer is maintained by Pima County. Click here to visit Pima County's Open Data site. Click here to visit Pima County's GIS Library metadata. PurposeThis layer was developed to show base flood elevation in Pima County, Arizona.Dataset ClassificationLevel 0 - OpenKnown UsesThis layer is not in any known applications.Known Errors No known errorsContactPima County - GISdata@pima.govUpdate FrequencyAs Needed