blankblank blank

Archive for December, 2008

Snow Cover Maps

Published by
Leszek Pawlowicz
 in data, global warming and KML. 2 Comments

So, the week of December 15-19, when I was supposed to be out doing field surveys in northern Arizona, we got snow. A lot of snow. And it kept going until about December 26th. It’s kind of hard to do a field survey when the ground is covered with snow, but I’ve been hoping the recent bout of warm weather would melt that snow quickly, and let me get back out in the field.

To monitor that situation, I’ve been consulting the US National Weather Service’s National Operational Hydrological Remote Sensing Center (with the snappy acronym NOHRSC). At this time of year, they supply a large number of snow-related data products, including:

Continue reading ‘Snow Cover Maps’




Battle KML Time Animations For Google Earth

Published by
Leszek Pawlowicz
 in Google Earth and KML. 3 Comments

Professor Peter Guth of the US Naval Academy, author of the first-rate terrain analysis and GIS program MicroDEM, writes to let me know that the final projects of one of his classes are available online. Among the projects are KML files for a number of historic battles, including time animations for Antietam, the Battle Of The Bulge, and Dien Bien Phu. These combine both actual historical situation maps as image overlays, and placemarks for unit positions:

Battle Of The Bulge in Google Earth

While you can click the “Play” button on the time animation control, I find it easier to follow the animation by manually moving the time slider over from left to right to follow the progress of the battle.




Google Earth Plus – RIP

Published by
Leszek Pawlowicz
 in Google Earth. 1 Comment

Not exactly new information anymore, but a few weeks ago, Google discontinued Google Earth Plus, their $20/year enhanced version of the free Google Earth program. These enhancements included:

  1. Enhanced performance – a faster download speed for data.
  2. Printing – A 40% improvement in printing quality (1400 pixels versus 1000 pixels).
  3. GPS Data Import (read only) – Download waypoint, track and route data directly into GE from a GPS
  4. Real-Time GPS Tracking – Put an icon in Google Earth to mark your current position as measured by a connected GPS.
  5. Spreadsheet data import – Import a .csv file with coordinates into Google Earth, and do address coordinate lookup (geocoding) as well.
  6. Advertisements – Optional in the Plus version.

One of the very first posts I did on this blog was on Google Earth Plus, but in a bit of foreshadowing, it was titled “Google Earth Plus – Do You Really Need It?”. It kicked off a multipart series describing ways you could duplicate, and even exceed, most of the important capabilities of Google Earth Plus using free or inexpensive software. Even though Google has dropped the Plus version, it’s steering people who need its capabilities to the $400 Pro version, which in addition to spreadsheet import allows opening GIS data like shapefiles and georeferenced imagery. I’ve covered programs that mimic some of those functions, like converting shapefiles to KML format, and creating Google Earth image overlays from georeferenced imagery; I’ll be covering some cheap and free options for creating image superoverlays before too long. And while Google says they will add GPS tracking to the free version of Google Earth in the near future, my Google Earth Plus For Free series covers several options available now, and I’ll have a post with two more options soon. For that matter, just take a look through the Google Earth category on this blog for dozens of useful Google Earth data tools that do things that no version of Google Earth can do, like export KML files to GPS receivers.




Tiny Geocoder

Published by
Leszek Pawlowicz
 in geocoding and Google Maps. 1 Comment

Tiny Geocoder is a small, simple web geocoder; type in an address or geographic location, and get back the approximate latitude/longitude for that location, and a Google Map view with that location plotted:

12-1-2008-10.03.26 AM

If you have a Google Map API key (free), you can generate code to create a static link to this map (static meaning just the image itself, not scrollable or zoomable).

And for web gearheads, there’s a simple and free API available for geocoding and reverse geocoding. Here’s an example of geocoding for Provo, Utah, and reverse geocoding for 37,-110.




Embeddable Visited States/Countries Image

Published by
Leszek Pawlowicz
 in cartography and data. Closed

At the Visited Countries site, fill in a checklist for a list of US states, Indian states, or world nations:

12-1-2008-9.07.36 AM

and get back a link to an image you can embed on your website or blog:


visited 36 states (72%)
Create your own visited map of The United States or try another Douwe Osinga project

Guess I need to spend some time in the Plains states :). There’s also a button which leds you embed the map directly into your Facebook page. For a site that creates a similar KML file for Google Earth, try Color Your Map.

Via Cartophilia.




Online Traveling Salesman Problem Solver

Published by
Leszek Pawlowicz
 in GIS, Google Maps and Web apps. 2 Comments

Wikipedia defines the “Traveling Salesman Problem” this way:

… given a number of cities and the costs of travelling from any city to any other city, what is the least-cost round-trip route that visits each city exactly once and then returns to the starting city?

You can substitute “address” for “city”, making this an intra-urban travel problem. The OptiMap website solves this problem automatically for up to 24 locations (“nodes”). You can enter the nodes by clicking in a Google Maps interface:

12-1-2008-7.25.50 PM

You can also enter address nodes individually using the “Add Location By Address” box. Even better, you can add text lists of addresses or coordinates (latitude/longitude) by clicking on the “Bulk add by address or (lat, lng).” link, then copying and pasting the list into the text box that shows up. Latitude/longitude should be in decimal format, one set on each line, separated by commas and surrounded by parentheses, e.g. (35.333, –110.254). You can also specify only walking directions, and avoiding highways. The first node or address entered is always considered to be the starting point.

When you’re done entering nodes, click on “Calculate Fastest Roundtrip” to solve the problem for a round-trip that ends where you started:

12-1-2008-7.26.28 PM

You’ll also get a set of Google Maps driving directions for the trip shown in the solution map. By clicking on the “Toggle raw path output” button, you’ll also get a text list of latitude/longitude coordinates in sequence for this route that you could convert into a GPS route:

12-1-2008-7.32.31 PM

The “Calculate Fastest A-Z Trip” works in a similar fashion, but for a one-way trip, where the first address/node you entered is taken as the start “A”, and the last address/node is the destination “Z”.

The technical background and source code are available on the OptiMap website, as are instructions on how to use this on your own website.




Embed Voice Annotation In Google Earth Placemarks

Published by
Leszek Pawlowicz
 in Google Earth and KML. 6 Comments

Digital Geography suggests a neat way to quickly add voice annotation to Google Earth placemarks. Record your message at Vocaroo.com, and when you’re done, click on the “Post on the internet” link. You can then copy and paste the HTML code directly into the placemark Description section: right-click on the placemark, choose Properties, click on the Description if it isn’t showing, then directly paste the Vocaroo code there. When you click on the placemark, the pop-up balloon will display a Flash player for your audio message.

For more advanced annotation, it would probably be better to record and edit your message in MP3 format, upload it to a web location, then try one of the free embeddable Flash MP3 players described on this page. For example, for the Google Reader MP3 player, take the code:

<embed type=”application/x-shockwave-flash” src=”http://www.google.com/reader/ui/3247397568-audio-player.swf?audioUrl=MP3_FILE_URL” width=”400″ height=”27″ allowscriptaccess=”never” quality=”best” bgcolor=”#ffffff” wmode=”window” flashvars=”playerMode=embedded” />

Note: Don’t copy and paste the above code, as that doesn’t work – copy and paste it from the code box on this website. Replace the “MP3_FILE_URL” section with the full link to your uploaded MP3 file, and then copy and paste the code into your placemark’s description section (same as above). Clicking on the placemark will bring up the balloon showing the MP3 player:

12-1-2008-9.50.34 AM

Just click on the play button to hear the message.




Two More Fire Mapping Websites

Published by
Leszek Pawlowicz
 in data. 1 Comment

From comments on my previous post on the Web Fire Mapper come two more links to fire-related mapping sites:

- The  Wildfire Information Portal (from Pitney-Bowes and the San Bernardino Sun) uses a Virtual Earth Interface to display wildfire-related layers with the transparency adjustable using sliders. Check a box to view a layer, click on the description to select it (Fire Boundaries in this case):

12-1-2008-8.38.12 AM

Below the layers panel, additional information and links to current data will appear:

12-1-2008-8.40.27 AM

Click on “Locate on the Map” for a data entry, and the map display will zoom in to the selected area:

12-1-2008-8.42.16 AM

There’s a link to a video tutorial at upper right. It’s definitely California-oriented, and the only data currently visible is for that state, but the video indicates that the site displays data for the entire United States.

- From NOAA comes a viewer for their Satellite Services Division (SSD) Fire Detection Program, showing fire and smoke data for the US, Central America, and southern Canada:

12-1-2008-8.52.15 AM

The default coverage (“Analyzed Fires from Satellites”) is shown above, but additional data for Central and South America can be seen by checking the AVHRR and MODIS boxes, then clicking “Refresh Map” at the bottom of the layers section:

12-1-2008-8.58.07 AM

HTs to joelarso and amlohdi.