Archive

Archive for the ‘Earth Sciences’ Category

USGS Topographic Map Update

November 15th, 2009 2 comments

Looks like a lot of people are using the Google Earth USGS Topographic maps.  Couple updates that I thought I’d pass on.

First of all, I recompiled the index to be much easier to use.  You no longer have to navigate through two index levels.  Now, simply zoom down and the index will appear automatically as you navigate around the US.  Click on one of the map outlines to open up a window with a button to download the map.

At the same time, the new index fixes a major bug that prevented many maps from loading.  You should now be able to view all of the maps south of 48 latitude.  If you find one that doesn’t work, please let me know so I can fix it.  I hope to have the remaining maps north of 47 latitude done by next month.  When done, this collection will have about 55,000 maps (~150 gigabytes) available to view in Google Earth.  I’m also going to try to add Alaska.

Several people have asked about Canadian Topo Maps.  I have been downloading them and I could add them to the collection.  But I think those will be another 200-300 gigabytes, and I don’t want to push my luck with my web host.  So that project is on hold until I figure out a way to host them.  If you happen to have a 200-300 gigabytes of server space laying around and want to help out please contact me.

I have also added some instructions on the Google Earth USGS Topographic maps page to show you how these topographic maps can very easily be embedded on your own web page or blog using the Google Earth Browser Plugin.

Lastly, I am still working on my Historic Topographic Map collection.  I know there are some maps in that collection that are broken.  The update I’m working on will fix those and probably double or triple the number of historic topo maps in the collection.  Sorry, but no time frame on when that will roll out.  The historic maps are a lot more work than the current maps.

  • Share/Bookmark

Related posts

Categories: Announcements, Topographic Maps Tags: USGS

USGS Topographic Map Overlay

July 31st, 2009 3 comments

This overlay contains seamless topographic/land cover data for the entire Earth and a USGS Topographic Map overlay for the entire US, including Alaska and Hawaii.

Different map scales automatically load as you zoom in with the most detailed maps being available for the US.  Hill shading has been added to the maps giving them a 3D appearance.

USGS Topographic Maps

Download With Google Earth

Credits

ESRI ArcGIS Online Services

  • Share/Bookmark

Related posts

Historical T-Sheets

July 5th, 2009 No comments

Historical T-Sheets are shoreline maps that were created in the late 1800 to early 1900s for major waterways and coastal areas of the United States. The T-Sheets contain information such as locations of buildings, names of shoreline features, and detailed descriptions of shorelines.

This collection contains over 250 maps covering the following locations:

  • Puget Sound, Washington
  • Hawaiian Islands of Oahu, Maui and Kauai
  • Mississippi coast line
  • Everglades area, Florida
  • San Francisco Bay, California

These maps typically range in size between 1 and 5 megabytes. However, there are a few that are over 15 megabytes. These might take a few minutes to load, depending on the speed of your Internet connection. While they are loading, it will appear that nothing is happening. Just be patient and they will eventually load.

If you know of any other sources of online historical T-Sheets, please post a comment and I’ll add them to the collection.

Historic T-Sheets

Download With Google Earth

Credits

Google Earth Library

University of Hawaii

US Coast Survey of San Francisco Bay

USGS Open File Report 02-204

Mississippi Office of Geology

Puget Sound River History Project

  • Share/Bookmark

Related posts