DroughtView

Drought is an ever-growing concern within the United States and Mexico. Extended periods of below-average precipitation can adversely affect agricultural production and ecosystems, impact local water resources and create conditions prime for wildfire. Seasonal and interannual vegetation and precipitation dynamics, including drought, can be monitored and examined by a variety of data sources and tools.

 DroughtView  is an online satellite time series and environmental data visualization tool and a resource for scientists, natural resource managers and the public. It contextualizes and brings a remote sensing perspective to drought impact assessments.

You can view data on DroughtView in one of three ways.

Navigational tools can be found in the top right hand corner of DroughtView. You can select your data, product, zoom level and Image Overlay Opacity.

These tools allow the user to draw a rectangle or a point. Then, these drawn features have a bubble giving the user an option to display timeseries of NDVI and EVI data from MODIS and VIIRS as well as Annual Productivity data . Select the desired timeseries, and click "Get Timeseries!' This will open a tab at the bottom of the screen that has an interactive chart. Click and drag on a region on the chart to zoom into that period. Right click to zoom out. You can also download the timeseries that is displayed on the chart using the link on the bottom of the screen.

Normalized Difference Vegetation Index (NDVI), and Enhanced Vegetation Index (EVI) are viewable on DroughtView.

· 250-meter 16-day composite Moderate-resolution Imaging Spectroradiometer (MODIS) imagery from 2000 to the present.

· 500-meter 8-day composite and Visible Infrared Imaging Radiometer Suite (VIIRS) from 2012 to the present.

Vegetation images are colored from tan (less vegetation) to dark green (dense vegetation).

Creation of difference from average, previous period and previous year greenness products provide the user with a proxy for drought conditions and insight on the secondary impacts of drought, such as wildfire.

Difference images are colored from orange to blue. Orange areas are less green compared to the overall average, the previous year or the previous period, while blue areas are more green. White areas experienced no change.

The Cloud/Snow mask allows you to determine the quality of the data (e.g. good and marginal data) aiding in the interpretation of the vegetation images for each period. The extent of the snow pack can also be estimated using this information.

The Drought Monitor raster overlay highlights regions currently in drought conditions. Darker shades of red indicate greater levels of drought.

Precipitation information is calculated using the Parameter-elevation Regressions on Independent Slopes Model (PRISM). You can visualize the total amount of rainfall since the beginning of the water year. You can also examine departure from precipitation totals.

You can select underlying basemaps, climate products and vector data by clicking the stack icon located in the top corner of each panel.

Vector features can be overlaid onto the satellite images. The map features include roads, cities, watershed boundaries, management agencies and range allotments. Some vector overlays are scale dependent becoming more detailed as you zoom in.

As we continue to develop this resource we welcome any feedback you would like to provide.

Data provided by NOAA/NCEI, NASA, PRISM Group, USGS and Land Processes Distributed Active Archive Center (LP DAAC). Contributions and funding provided by the Arizona Remote Sensing Center (ARSC), School of Natural Resources and the Environment, Environmental Science, Climate Assessment for the Southwest (CLIMAS), College of Agriculture and Life Sciences Cooperative Extension, Water, Environmental, and Energy Solutions (WEES) and the Salt River Project (SRP). The user interface for DroughtView was built using the  Leaflet  JavaScript online maps library, making use of the core Leaflet library, third-party plugins, and custom JavaScript codes to accomplish the functionality and look and feel of the tool. The map data are from a variety of online sources, but many maps are generated and served using map servers at the Arizona Remote Sensing Center.

 Visit DroughtView by clicking here.