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ABSTRACT: Samples from 107 piñon pines (Pinns edulis) at four sites were used to develop a proxy record of annual (June to June) precipitation spanning the 1226 to 2001 AD interval for the Uinta Basin Watershed of northeastern Utah. The reconstruction reveals significant precipitation variability at interannual to decadal scales. Single-year dry events before the instrumental period tended to be more severe than those after 1900. In general, decadal scale dry events were longer and more severe prior to 1900. In particular, dry events in the late 13th, 16th, and 18th Centuries surpass the magnitude and duration of droughts seen in the Uinta Basin after 1900. The last four decades of the 20th Century also represent...
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This set of sixteen Landsat Thematic Mapper (TM)and Operational Land Imager (OLI)(Path 014 and Rows 032 and 033) surface reflectance data sets were collected between 2000 and 2015. This data presents a time-series analysis that uses linear spectral unmixing of composite Normalized Difference Vegetation Index, Normalized Difference Water Index, and Normalized Difference Soil Index data, to estimate the percentages of marsh vegetation, water, and exposed marsh substrate on the New Jersey intracoastal marshes. We used the composition of the marshes in terms of the percentage of marsh vegetation, water, and marsh substrate to produce Marsh Surface Condition Index (MSCI) maps consisting of three classes of marshes: severely...
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Understanding how different crops use water over time is essential for planning and managing water allocation, water rights, and agricultural production. The main objective of this paper is to characterize the spatiotemporal dynamics of crop water use in the Central Valley of California using Landsat-based annual actual evapotranspiration (ETa) from 2008-2018 derived from the Operational Simplified Surface Energy Balance (SSEBop) model. Crop water use for ten crops are characterized at multiple scales. The Mann-Kendall trend analysis revealed a significant increase in area cultivated with almonds and their water use, with an annual rate of change of 16,327 hectares in area and 13,488 ha-m in water use. Conversely,...
This USGS Data Release represents geospatial data sets which were created to produce an Unvegetated to Vegetated Ratio (UVVR) for coastal wetlands of the conterminous United States (2014-2018). The following listed image products were generated 1) Annual spatial datasets (rasters) from 2014 to 2018 each containing 4 bands (Band 1: Unvegetated land fraction; Band 2: Vegetated land fraction; Band 3: Water fraction; Band 4: UVVR clipped into 3 coastal regions (Atlantic (ATL) Gulf of Mexico (GOM) and Pacific (PAC). 2) Calibration/Validation Datasets - datasets which were used in the calibration and validation of the above datasets 3) Mean of masked, multiyear composite - Mean vegetated fraction in coastal wetlands in...
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These are two land cover datasets derived from Landsat Thematic Mapper and Operational Land Imager (spatial resolution 30-m)Path 014 and Rows 032 and 033 surface reflectance data collected on July 14, 2011 and July 19, 2013, before and after Hurricane Sandy made landfall near Brigantine, New Jersey on October 29, 2012. The two land cover data sets provide a means of evaluating the effect of Hurricane Sandy of data sets collected at times that represent or approach peak vegetation growth. The most accurate results of the land cover classification are based on twelve classes, some of which occur adjacent to the marshes but not on the New Jersey intracoastal marshes. Twelve classes were used in the supervised maximum...
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This USGS Data Release represents geospatial data sets that were created for the analysis of the effect of Hurricane Sandy on New Jersey Atlantic Coastal Marshes. The following listed image products were generated: 1) Fifteen marsh surface condition index (MSCI) data sets were calculated from yearly summer collections of ETM+ image data from 2000 to 2015. Three classes described the results of the MSCI mapping; classs1-severely impacted, class 2-moderately impacted, and class 3-intact marsh. 2) Marsh change data product using Landsat images of July 14, 2011 (before) and July 19, 2013 (after) Hurricane Sandy is based on the difference in the percentage of vegetation. It shows a pattern of an increasing loss of marsh...
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The change detection data is the classified difference in the percentage of vegetation on the July 14, 2011 Landsat Thematic Mapper(TM) data set collected before Hurricane Sandy and the July 19, 2013 Landsat Operational Land Imager (OLI)data set collected after Hurricane Sandy. Hurricane Sandy made landfall near Brigandine, New Jersey on October 29, 2012. The actual difference in the percentage of vegetation is used in the calculation, not the three-class classification that is the basis of the Marsh Surface Condition Index data. The eleven classes consist of five classes (5-20%,>20%-40%,>40%-60%,>60%-80%,>80%)with decreases in the percentage of vegetation cover after Hurricane Sandy, Three classes (5-20%,>20%-40%,>40%-60%)with...
Samples from 107 piñon pines (Pinns edulis) at four sites were used to develop a proxy record of annual (June to June) precipitation spanning the 1226 to 2001 AD interval for the Uinta Basin Watershed of northeastern Utah. The reconstruction reveals significant precipitation variability at interannual to decadal scales. Single-year dry events before the instrumental period tended to be more severe than those after 1900. In general, decadal scale dry events were longer and more severe prior to 1900. In particular, dry events in the late 13th, 16th, and 18th Centuries surpass the magnitude and duration of droughts seen in the Uinta Basin after 1900. The last four decades of the 20th Century also represent one of the...
Water resource planning is based primarily on 20th century instrumental records of climate and streamflow. These records are limited in length to approximately 100 years, in the best cases, and can reflect only a portion of the range of natural variability. The instrumental record neither can be used to gage the unusualness of 20th Century extreme low flow events, nor does it allow the detection of low-frequency variability that may underlie short-term variations in flow. In this study, tree rings are used to reconstruct mean annual streamflow for Middle Boulder Creek in the Colorado Front Range, a semi-arid region of rapid growth and development. The reconstruction is based on a stepwise regression equation that...


    map background search result map search result map Analysis of the effect of Hurricane Sandy on New Jersey Atlantic coastal marshes based on landsat thematic mapper and operational land imager data: 2000-2015 Marsh surface condition index dataset Marsh change dataset Land cover classification dataset Crop Water Use in the Central Valley of California using Landsat-derived evapotranspiration An Unvegetated to Vegetated Ratio (UVVR) for coastal wetlands of the Conterminous United States (2014-2018) Analysis of the effect of Hurricane Sandy on New Jersey Atlantic coastal marshes based on landsat thematic mapper and operational land imager data: 2000-2015 Marsh surface condition index dataset Marsh change dataset Land cover classification dataset Crop Water Use in the Central Valley of California using Landsat-derived evapotranspiration An Unvegetated to Vegetated Ratio (UVVR) for coastal wetlands of the Conterminous United States (2014-2018)