Spring 2012 Earliest on Record plus 1 more

[USGS Newsroom <oc_web@xxxxxxxx>]

Title: USGS Newsroom

Spring 2012 Earliest on Record plus 1 more

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Spring 2012 Earliest on Record

Posted: 15 May 2013 10:25 AM PDT

March 2012 set records for warm temperatures that promoted early leafing and flowering across large areas of the United States. A team of scientists at the USA National Phenology Network, which is sponsored by the U.S. Geological Survey, have published a study which shows that 2012 was the earliest spring over the 48 U.S. states since 1900 when systematic weather data began to be available for the entire area. 

Phenology is the study of recurring plant and animal life cycle stages, especially their timing and relationships with weather and climate. Assessing the severity and impacts of such extreme climatic events, either in the past or as they happen, requires consistent indicators of variability and change that can be mapped both nationally and historically. 

The USA National Phenology Network provides a suite of "spring indices" based on the accumulated warmth needed to end dormancy and initiate growth in many native and cultivated plants. These complex, evidence-based algorithms can be calculated for any weather station that records daily maximum and minimum temperatures. Spring indices are independently validated using historical observations of leafing and flowering in lilac and honeysuckle nationwide. 

The historical trend of spring indices suggests that the 2012 growing season advanced as much as 20-30 days in the East and Midwest from the 1900-2012 long-term mean.  

"The results of this study clearly demonstrate the great importance of long-term monitoring of natural processes. A long record allows us to identify patterns of change that we might otherwise miss," said Suzette Kimball, acting USGS Director. 

Today the response of vegetation to temperature and precipitation can be readily observed across wide areas by Earth-observing satellites at intervals of only a few days. USGS scientist Julio Betancourt, a co-author of the study, noted, "Indicators such as spring indices and satellite-based evaluations of vegetation growth will become essential tools for assessing climate variability and change and their impacts." 

Satellite data show that the cumulative effects of the unusually early 2012 spring were most pronounced across the Corn Belt, the western Great Lakes region, and the northeastern U.S. 

The beneficial effects of spring's quick start in 2012 were subsequently offset by a late spring frost and summer drought. In fact, the unusually early spring combined with late frosts in April to produce a so-called "false spring" that damaged fruit trees across the Upper Midwest and Great Lakes regions. 

The study appears in EOS, Transactions of the American Geophysical Union. 

Learn more 

• USA National Phenology Network 
• Vegetation Drought Response Index (VegDRI) 
• USGS Climate and Land Use Change Programs 
• USGS Ecosystems Programs

Revised Kentucky and Tennessee Maps Reveal New Design

Posted: 15 May 2013 09:00 AM PDT

Newly designed maps covering Kentucky and Tennessee are now available online for free download

US Topo maps now have a crisper, cleaner design - enhancing readability of maps for online and printed use. Map symbols are easier to read over the digital aerial photograph layer whether the imagery is turned on or off. Improvements to symbol definitions (color, line thickness, line symbols, area fills), layer order, and annotation fonts are additional features of this supplemental release. Users can now adjust the transparency for some features and layers to increase visibility of multiple competing layers.

This new design is launched on new US Topo quadrangles for Kentucky (671 maps) and Tennessee (694 maps), which replace the first edition US Topo maps for those states. The replaced maps will be added to the USGS Historical Topographic Map Collection and are also available for free download from The National Map and the USGS Map Store website. 

"The new Kentucky and Tennessee US Topo maps demonstrate our commitment to improving the product design to meet our users’ needs", said Mark DeMulder, Director of the USGS National Geospatial Program. "I encourage you to download these maps, compare them against the previous US Topo map and drop us your comments on the US Topo map product. Your input is important to us."

US Topo maps are updated every three years, with the initial round completed last September. Maps for Hawaii are currently in production with Alaska production starting later this year.

Re-design enhancements and new features:

• Crisper, cleaner design improves online and printed readability while retaining the look and feel of traditional USGS topographic maps
• New functional road classification schema has been applied
• A slight screening (transparency) has been applied to some features to enhance visibility of multiple competing layers
• Updated free fonts that support diacritics
• New PDF Legend attachment
• Metadata formatted to support multiple browsers
• New shaded relief layer for enhanced view of the terrain
• Military installation boundaries, post offices and cemeteries

US Topo maps are created from geographic datasets in The National Map, and deliver visible content such as high-resolution aerial photography, which was not available on older paper-based topographic maps. The new US Topo maps provide modern technical advantages that support wider and faster public distribution and on-screen geographic analysis tools for users.

The new digital electronic topographic maps are delivered in GeoPDF image software format and may be viewed using Adobe Reader, available as a no cost download.

For more information, go to: http://nationalmap.gov/ustopo/