New lidar of the home area

Lidar provides one of the best mapping tools currently available.  Until this week, the best data for my home region had less than one point per square meter, and was acquired in 2011.  I just found that the state now has data with at least 10 times better point density, and which was acquired in 2017.

The 2011 survey.

The 2017 survey.

Selected points to highlight the improvements.  (A) you can now see the tombstones in the cemetery; (B) the footbridge has much improved resolution; (C) the parking garage is under construction (maybe caught during a stop work order?); (D) Hopper Hall has begun constuction, removing a parking lot; 2017 was a good time to be in Morocco and not have to deal with the parking woes); and (E) the cars in the remaining parking lot show much better detail than in the 2011 survey.

Difference map between 2011 and 2017.  In magenta points were 5 or more meters tallker in 2017; from the shapes these are trees.   The added elevations from the parking garage are in red and yellow.  Points in blow saw 5 or more meter lower elevations during the period, and these are almost all trees.

Overall the elevations are very similar for most areas in the two surveys.  I plan to rerun my storm surge flooding model of Annapolis  to see if it makes any difference, and to cover a larger area.  The model uses a post-Isabel data set that may not  be publicly available.