Look back in time – or at least 23 years

HPOWEB relies heavily on the fantastic, true-color, 6-inch-per-pixel, aerial imagery served up by NC One Map.  In 2010 the entire state was flown, and since 2012 a separate quarter of the state’s 100 counties have been updated with new imagery each year.  NC One Map will soon release 2016 imagery of the coastal counties.

NC One Map also provides statewide coverage from 1998 and 1993, as well as a composite image of the latest imagery for any area to which you are zoomed in.  We have decided to make these imagery datasets more easily available within HPOWEB by modifying the Background View grid.

new_background_views_generalaudience

The General Audience version of HPOWEB (accessible here) now shows the three statewide imagery layers on the second line of the grid, while the most recent aerial imagery layer is in the middle top row.

The 1998 imagery is infrared, which makes vegetation appear reddish and water features blackish.  It can often help distinguish human-made objects from surrounding trees.

The 1993 imagery is black and white and of a much lower spatial resolution than the recent imagery.  Still, it can help locate structures no longer extant – or confirm historic field patterns in an area lost to development.

new_background_views_advanceduser

The Advanced User version of HPOWEB (accessible here) also displays these four imagery layers in the same positions, but note that a few additional background views – including two more topographic views and a Dark Gray basemap – are available in this version.

The individual images of the “Most recent aerial” may range from 2011-2015, and this date range will roll year by year as new imagery is flown.  For instance, the coastal counties had imagery flown in 2011, but when the 2016 images become available, the date range will be listed as 2012-2016.  (You can see a map of which counties were flown each year, here.)

We hope you find these changes useful!

 

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