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Saroo Brierley’s story to be made into a movie

jeu 06-11-2014

Back in 2012 we brought you the story of Saroo Brierley who as a child got lost on a train in India, was adopted by a Tasmanian couple and, as an adult, found his way home using Google Earth. We followed up with more details in this post and in 2013, Google created a YouTube video about it which we covered here. Saroo has also written a book about his experience titled “A Long Way Home”.

Now the story is to be made into a movie called ‘Lion’ with Nicole Kidman and Dev Patel (of Slumdog Millionaire fame) expected to star in it. See this story for more details.

Saroo Brierley’s book A Long Way Home now to be made into a movie.

The post Saroo Brierley’s story to be made into a movie appeared first on Google Earth Blog.

Catégories: Sites Anglophones

New Google Earth Imagery – November 3rd, 2014

mer 05-11-2014

In our month end post we mentioned that GEB reader ‘munden’ had found updated imagery. Thanks also to GEB readers ‘Mapmaker’, Frank, Georg, and Sladys for letting us know about additional areas in the comments and via email. Now, Google have updated their ‘latest Google Earth Imagery’ map, showing the date 3rd November 2014. However, the aforementioned areas are not part of this current update, so it seems that once again Google have skipped telling us about an update.

I found out about the current update because I got an email from Google’s Follow Your World app that lets you monitor locations you are interested in and my home town of Livingstone, Zambia, was part of the update.

Latest Google Earth Imagery map – November 3rd, 2014. Larger version.

To view the map in Google Earth you can download this KML.

[Update: Thank you to GEB reader Maarten for letting us know that there was an update that we missed for October 21st, 2014 and for sending us a screen shot as seen below. ]

Google Earth Imagery map – October 21st, 2014. Larger version.

The post New Google Earth Imagery – November 3rd, 2014 appeared first on Google Earth Blog.

Catégories: Sites Anglophones

Earth View – Google Chrome extension

mar 04-11-2014

Satellite imagery can be beautiful, and as a result, a number of people have used satellite imagery as art. For example, in 2010 we showed you the USGS “Earth as Art” collection, and earlier this year we talked about Roosmarijn Pallandt, who designs carpets using satellite imagery.

If you can’t get enough of satellite imagery, and you are a user of Google Chrome, there is a nice extension called Earth View (created by Google) that shows a different satellite image from Google Maps every time you open a new tab. I have been trying it out over the last couple of weeks, and although I missed some of the features of Chrome’s default ‘New Tab’ page, I am now used to it and really love the imagery. Find the Earth View extension in the Google Play store here.

Earth View shows you a different satellite image every time you open a new tab in Chrome.

I would like to see a number of additions to the extension, including:

  • The option to use it as a background to the default ‘New Tab’ page rather than replacing it altogether.
  • An ‘Open in Google Earth’ button in addition to the current links to Google Maps.
  • A similar product that works as either a desktop background changer, or screen saver, or both.
  • Occasional 3D scenery in addition to the top down satellite imagery.

If you have tried out the extension, what additions would you like to see?

The post Earth View – Google Chrome extension appeared first on Google Earth Blog.

Catégories: Sites Anglophones

Satellite font created from buildings

lun 03-11-2014

In the past people have found faces hidden in satellite imagery, and the German design studio Onformative even went so far as to write a program to scan the whole globe using face recognition software. We have looked at unusually shaped buildings before, including a building shaped like a swastika. We have also pointed you to’s collection of interestingly shaped pools.

A recent story in the news is about designer Yousuke Ozawa creating a font out of satellite images of buildings. See the full story here.

Satellite font by Yousuke Ozawa.

It turns out, however, that he is not the first to think of this. Back in 2008 we discovered via Google Maps Mania a clever site called geoGreeting that lets you send a message using letters made from buildings.

The intro-message on geoGreeting.

The post Satellite font created from buildings appeared first on Google Earth Blog.

Catégories: Sites Anglophones

The best of Google Earth for October 2014

ven 31-10-2014

The biggest story of the month was the release of Google Earth for Android version 8. Find Frank’s review of the changes and new features here. The most notable feature is a complete rewrite of the 3D engine.

Google have continued to add 3D imagery, the most notable additions being Berlin and Madrid. If you haven’t already done so, be sure to download the KML of 3D areas from this post. A big thanks to all the GEB readers that continue to contribute towards it.

Berlin and Madrid get the new 3D.

Although, as of this writing, Google’s map of imagery updates has not been updated since the 4th of October, GEB reader ‘munden’ has told us that a number of imagery updates have been made, including:

Bahrain: Manama
China: Dalian, Xiaoping Island.
Denmark: Rosensgade, Aarhus.
Russia: Severormorsk.
Estonia: Tallinn.
Egypt: Port Said, Ismailia, Cairo, Alexandria.
Turkey: Izmir, Körfez, Tavşanlı, Maltepe, Çayırova, Adana.
Guam: Barrigada.
Iran: Bandar Abbas, Tehran.
Japan: Soma, Izumi, Sendai and a strip of imagery along the port of Himeji.
New Zealand: Glorit, Hobbiton (search will show it at Matamata, Waikato).
Russia: Bukhta Krasheninnikova.

[Update: see comments below post for additional areas found by GEB readers. ]

My favorite stories of the month were:

Google’s Skybox for Good program, which provides nonprofits with access to satellite imagery from Skybox Imaging’s satellites.

The Seti Institute’s maps of various planets and moons, which allow us to transform Google Earth into a solar system explorer.

The USGS 3D Elevation Program that promises significantly enhanced elevation data for the US.

What were your favorite stories?

The post The best of Google Earth for October 2014 appeared first on Google Earth Blog.

Catégories: Sites Anglophones

Animating historical imagery using the Google Earth plugin

jeu 30-10-2014

Earlier this month we showed you a gif animation of the historical imagery of Europe. It was created by taking screenshots of Google Earth then combining them into an animated gif. However, doing that for every continent would be tedious, so instead we have decided to do it using the Google Earth plugin.

Although we have expressed concern about the future of the GE plugin, and a number of sites that used to use the plugin are starting to move to alternatives, it is, nevertheless, still a very useful tool.

If you have a browser that supports the Google Earth plugin you should see the Earth below. Rotate it to your favorite continent and click start. You should see the historical imagery toolbar in the top left corner of the plugin. If nothing happens, try refreshing the page and clicking start again.

input {width:75px;} The animation starts in this year. Each step will be a decade: When this year is reached each following step will be a year: When this year is reached each following step will be a month: Length of each step in milliseconds: Start Stop


For most parts of the world, the above settings will work fine, but we included them in case you wish to tweak them a bit for specific locations. Also try zooming in to see effects reminiscent of Google’s Timelapse.

If your browser does not support the plugin then you can see the results in the YouTube video below.

The post Animating historical imagery using the Google Earth plugin appeared first on Google Earth Blog.

Catégories: Sites Anglophones

Halloween Earth

mer 29-10-2014

With Halloween on Friday, this is a good time to get your pumpkin decorations finished. If you are having trouble covering your house with pumpkins, then why not cover the whole earth with one instead? Back in 2006, Frank created an Earth sized pumpkin that you can download here and view in Google Earth.

Since most of our regular readers will have already seen the Pumpkin Google Earth before, we thought we would add a little extra this year, so grab this KML as well for a bit more Halloween atmosphere. For the best effect be sure to turn off the “Atmosphere”. There are four backgrounds included so try them all out. It is relatively easy to modify the KML and put in your own background images. If you use an image with writing on, be sure to save it as a mirror image.

Images obtained from:

The post Halloween Earth appeared first on Google Earth Blog.

Catégories: Sites Anglophones

Satellogic planning to achieve global coverage with live video and pictures

mar 28-10-2014

Yesterday we talked about Skybox, which is owned by Google and currently has two satellites, but is planning a constellation of 24. When we talked about their gif animations of the Burning Man festival, we also pointed out a YouTube video that they say is the first HD resolution video of Earth from space. More videos from Skybox can also be found here

We recently came across this interesting article about a startup, Satellogic, that is planning to launch hundreds of satellites and provide live video and regular pictures with global coverage.

From their website:

We are building a constellation of satellites to image any spot on earth every few minutes.”

It won’t be as high resolution as the best images from Digital Globe, and we must remember that at any given time much of the globe is obscured by cloud cover, but global coverage with live video or pictures every few minutes is still exciting stuff!

BugSat-1 in a clean room.

The internals of a satellite.

The post Satellogic planning to achieve global coverage with live video and pictures appeared first on Google Earth Blog.

Catégories: Sites Anglophones

Skybox for Good

lun 27-10-2014

Back in June 2014, Google acquired Skybox Imaging. In September, Skybox provided an impressive demonstration of their capabilities by capturing images of the Burning Man festival and producing animated gifs of its progress.

Now Skybox has announced the Skybox for Good program. Under the new program Skybox will work with non-profits to provide fresh satellite imagery where they need it. Of special interest is the fact that the images obtained via this program are being released under a Creative Commons By Attribution license (CC BY 4.0), which allows anyone to view and use the images.

Skybox has provided a map of images collected so far under the program that you can find here. You can also view it in Google Earth using this KML file.

Mining in the Appalachians – see the Skybox blog for details.

The post Skybox for Good appeared first on Google Earth Blog.

Catégories: Sites Anglophones

Review of Google Earth for Android Version 8

ven 24-10-2014

As mentioned in my previous post, Google recently announced a new version of Google Earth for Android. This version ( is a complete re-write of the underlying Google Earth 3D model, and now has access to unified mapping data used by Google Maps and this new version of Google Earth. This means the most current available mapping data can now be viewed in this version of Google Earth (Google Earth version 7 on all the other platforms is based on less current data). Version 8 also adds some enhanced 3D rendering and improves some aspects of KML support. These things are good news for what they portend for future releases on the other platforms. So, although this release is not everything we hoped for (see below), we are happy to see this new version released.

We can understand why Google would want to start development of Google Earth version 8 on Android first. The mobile version of Google Earth has far fewer features than the desktop versions, making it easier to develop a smaller set of features. None of the power features that allow you to create your own maps on the desktop version are available on the mobile version. Similarly, the more powerful KML features such as time animations, network links, GPS tracks, and many others are not yet supported on the mobile platform. This is true on the new version 8 release as well. Not only that, but this new release is missing a few important features from the previous release on mobile. It seems Google rushed this new release out as there are a number of bugs.

This review will show screenshots of the previous mobile version next to the new release. Version 7 will be on the left, and version 8 on the right in most cases. My two devices used for testing (a Samsung Galaxy S4 for version 7, and a Nexus 7 for version 8) have different aspect ratios, so they will look somewhat different.

Atmospheric effects

The new version 8 includes a stronger rendering effect for the atmosphere similar to the one on the desktop version of Google Earth introduced several versions ago. While this gives a more realistic effect in some ways, Google needs to add an option to turn it off. The reason is that you can’t view data clearly, especially while viewing more horizontally. Also, the colors of the imagery are subdued because of the atmospheric effect and they look dull and “grey”. I see the atmosphere effects as a “gee whiz” effect that distracts from the important map data. In real life, the atmosphere gets clearer or more hazy depending on weather. Lets give the user that option. See screenshot comparison of version 7 (left), version 8 (right).

Atmosphere (7 left, 8 right)
(click for larger)

New 3D model of Earth

Since Google Earth was first released, the rendering of the geometric model of the Earth had a flaw when viewing the poles. It was particularly bad when Google Earth was first released, but Google made some improvements in later versions. Google Earth’s developers told me years ago they hoped to someday re-write the model so you could view the poles. The new version 8 does address this and the renderings are free of visual anomalies. But, there is still some weirdness to how you zoom in and view the poles with the current interface. You can’t zoom straight down to the poles, you have to tilt your view and zoom towards them to see them. But, overall it is a much more pleasing view of the poles and proves this is a new geometric model for Google Earth. The south pole has a strange white spot (I guess they have no imagery there), but the north pole is fine. In version 7 you see lots of rays shooting out from the poles, but the new version shows the imagery fine. Unfortunately, the screenshots of the south pole are hard to make out due to lack of contrast with all the ice.

South pole

Layer choices

Version 7 of the mobile version of Google Earth had already combined the layers of Borders and Labels into one choice. In version 8 they have gone a step further and combined Road, Borders and Labels into one choice. This is a mistake in my opinion because the user has less control over their mapping data. Not only that, but the vectors drawn in version 8 are not yet optimized when compared to version 7 and draw and/or load slower. This is especially obvious when zooming in and out. Also, the new borders and labels in version 8 coming from the Google Maps data are black and white and do not provide as much information as the Google Earth borders and labels. Google Earth 7 border layers show more data, and different colors, for things like oceans and sea names, country names verses states and cities, etc. The new version 8 labels are pretty much plain white and not as informative. However, they are more consistent with the Google Maps platform (which I also don’t like). A very important missing layer in version 8 is “3D Buildings”. You can’t turn them off in version 8, which is a mistake. The 3D buildings layer loads a lot of data which, if you are on a limited 3G bandwidth plan, means it could cost you if you use Google Earth to view cities with 3D data. It also could slow down your view when you just want to view the imagery or Street View data for that location. Other missing layers include: Ocean, Places, and Businesses. The screenshots below compare the labels and border data between the two versions.

Borders and labels

KML Support

Previous versions of Google Earth for mobile were difficult to load KML. However, we recently discovered that recent versions of Chrome for Android now allow you to load KML from web links (like those found on GEB) directly from the browser into either Google Earth 7 or the new version 8. The new version also gives you the new option to load KML from Google Drive, in addition to the options from Maps Gallery, Maps Engine (which will be the new My Maps), and your Google+ photos (that have been geotagged). Some of the Google Maps Gallery choices do not work properly because of limited KML functionality support on the mobile platform. KML support in version 8 is also a bit buggy at this point. I found many KMLs that should work to have errors (which have been reported, and Google says they will work on them). One particularly annoying bug is that KML lines go transparent when you tilt the view, so in an example of GPS tracks of a ski vacation much of the tracks are not visible in version 8, whereas version 7 shows them fine. See version 7 above version 8 in the screenshots below.

Ski tracks KML

In Summary

Google Earth Version 8 for Android is based on a new geometric 3D model of the Earth, and accesses the more current and more accurate data of the Google Maps databases. According to Google, this new version is the first overhaul to Google Earth’s 3D model in 10 years.

Version 8 does make it easier to load KML, although the limited support of KML features and rendering is disappointing. This version has fewer options to turn on/off mapping layers than even version 7 for mobile, so the layer features are a bit of a step backwards. But, hopefully Google will continue to advance the technology behind the mobile version and add new features and layers as it evolves.

We also sincerely hope Google puts even more effort behind the development of the desktop version 8. The desktop platform has suffered from the lack of access to more accurate mapping data improvements, and other development and bug fixes which is not good considering Google Earth is one of the world’s most popular applications. The desktop version of Google Earth also provides much more powerful features of KML, user data, map creation, APIs for developers, and much more. And lets face it, Google Earth looks awesome on the larger screens we use on non-mobile platforms!

The post Review of Google Earth for Android Version 8 appeared first on Google Earth Blog.

Catégories: Sites Anglophones

Partial Solar Eclipse October 23rd 2014

jeu 23-10-2014

There will be a partial solar eclipse later today October 23rd 2014. It will be visible over much of North America. We have looked at eclipses many time in the past, including: 2006, 2008 1,2, 2009, 2010,2012 and 2013.

Several of the sites or KMLs that we have pointed to in the past either no-longer work or do not include this eclipse – probably because it is only a partial eclipse. However, the HeyWhatsThat eclipse page, which uses the Google Earth plugin, still works correctly and will show you the path of today’s eclipse. Be sure to tick ‘penumbra’ near the bottom right. You can also watch the partial eclipse live on Slooh, an online community observatory. For more technical information about the eclipse see the NASA page

Eclipse track on HeyWhatsThat.

The post Partial Solar Eclipse October 23rd 2014 appeared first on Google Earth Blog.

Catégories: Sites Anglophones

Google Rewrites Google Earth for Android

jeu 23-10-2014

Google has announced a new version of Google Earth for Android that promises “an enhanced 3D experience, quicker updates to the map, and an easier way to view your KML files in Earth”. It has some interesting new rendering technology, and the ability more easily load KML files is an important step. I will be giving a more detailed look at the new Google Earth App for Android soon, including an analysis of the new rendering and KML support features. Here’s a screenshot Google provided of the new 3D look.

New Google Earth for Android

What is most significant about this announcement and release is that Google says this is the “first major 3D overhaul since Earth launched more than 10 years ago“. For the past couple of years, Google has not been making significant new updates to Google Earth. This is something we have been quite concerned about, since there hasn’t been a major update to the desktop version in almost 2 years. I wrote about these concerns in February, and Google’s Brian McClendon – who leads the Google Maps, Google Earth and other geographic products – promised they were planning to continue support for future Google Earth and KML development. This is the first step in delivering on the promise.

A significant hint at this new development effort is that the new Google Earth app now utilizes the Google Maps dataset. Always in the past, Google Maps and Google Earth used two different databases. That is why the roads and city names and other information often did not agree between the two products. The new Google Earth app definitely accesses current mapping data used in the Google Maps platform.

The new app doesn’t just have new data, it is a complete re-write to the underlying Google Earth underlying 3D model. That’s what they meant by an “overhaul“. I will explain more about this in the upcoming review, but we have discovered the entire geometric model is different. This is very significant and hints that Google is probably already working on developing a new desktop version of Google Earth that will utilize this new model and access the same unified database of mapping data! We are excited!

The post Google Rewrites Google Earth for Android appeared first on Google Earth Blog.

Catégories: Sites Anglophones

Jimmy John’s non-compete zones in Google Earth

mer 22-10-2014 has an interesting blog post about U.S. sandwich restaurant chain Jimmy John’s, which requires their deli employees to sign non-compete agreements. There is an online map provided, but it is best viewed in Google Earth by downloading this KML file.

Jimmy John’s non-compete zones.

We asked blog writer Sean Maday how the map and KML were made and he told us:

I pulled all of the store locations from the Jimmy John’s website and then used PostGIS to create a three mile buffer (circle) around each store. Then I dissolved the buffers to create a union of all overlapping polygons.”

So would it be possible to do something similar using just Google Earth? It would certainly not be easy. Google Earth is a fantastic product but is not a replacement for a professional Geographic Information System (GIS) program.

KML does not have a built in way to create circles. The best you can do in KML is a polygon with lots of points on the circumference of a circle. We found a couple of online tools that help you create a KML circle around a given location: kml4earth and thesamestory. Neither of them offer an easy way to take a table of coordinates and create a KML of circles.

As for creating a union of overlapping polygons, we can find no way to do it in Google Earth or with basic tools other than manually editing the KML file. The only real solution is a GIS program. We did find a free opensource GIS called Quantum GIS and instructions on how to use it to merge polygons, but it is not a small application and not easy to use if you have no experience in GIS. PostGIS that Sean used is open source but requires some GIS and SQL experience to use.

Perhaps one of our readers knows of an easy way to merge to KML polygons without the use of a GIS package?

The post Jimmy John’s non-compete zones in Google Earth appeared first on Google Earth Blog.

Catégories: Sites Anglophones

Google Solar System

mar 21-10-2014

We have in the past shown you how to turn Google Earth into various other planets including Saturn, Jupiter and Mars. Several of the models come from the Barnabu blog by James Stafford, who also created a comparison of the solar system’s moons, which we covered in 2007.

Now you can explore a number of the solar system’s planets and moons using imagery courtesy of NASA and USGS, which has been published on the Google Maps Gallery by the SETI Institute.

Simply pick a map from here then click the ‘View in Google Earth’ button at the lower right. Turn off any distracting Google Earth layers. Also note that many of the maps have multiple layers that can be turned on or off in Google Earth.

Jupiter’s Moon Io.

Topographic map of Venus.

The post Google Solar System appeared first on Google Earth Blog.

Catégories: Sites Anglophones

Using KML to change your field of view in Google Earth

lun 20-10-2014

Thank you to GEB reader Sebastien for letting us know that the Field of View can be adjusted in Google Earth by means of a tour. There are other techniques mentioned here such as a KML with transparent photo overlay, or changing an ini file, but the tour technique seems to be the easiest.

It is hard to describe the effects of changing the field of view, so instead we will just show you.

Google Earth with different fields of view.

In the above screen shots, the eye altitude varies from about 64,000 km with a field of view of 10°, to just 37 km with a field of view of 300°. Also, with the larger fields of view it is possible to zoom out a very long way from the earth, which has interesting effects on the background stars and galaxy. Using the 300° field of view and zooming in on an area with mountains or 3D buildings also has interesting effects.

3D buildings seen with a 300° field of view.

If you ever want to change the field of view yourself simply create a short tour in Google Earth, edit the KML and add <gx:horizFov>120</gx:horizFov> inside the <LookAt> tag, changing ‘120’ to your desired field of view.

Alternatively, just download one of the tours we have prepared for you, and if it doesn’t have your desired field of view, edit it in a text editor and adjust the number in the line with ‘gx:horizFov’. Here are the tours: 10°,30°,45°,60°,90°,120°,160°,200°,300°.

The field of view remains in effect until you either open a tour with another field of view, or restart Google Earth.

The post Using KML to change your field of view in Google Earth appeared first on Google Earth Blog.

Catégories: Sites Anglophones

Google Earth plugin gradually fading away

ven 17-10-2014

Due to the uncertain future of the Google Earth plugin, many prominent sites that used to use it have started to transition to other alternatives.

Here are three examples:

Ships 2 Career from

Back in 2009 released a fantastic free ship simulator using the Google Earth plugin. In 2011 it was upgraded to version 1.5.

However, the developer, Paul van Dinther, is now working on Ships 2 Career, which is entirely Google Maps based. Follow his progress on his Google+ page. We are sure that when it is released it will be an excellent game.

Ships 2 Career will be entirely Google Maps based.

GE Teach

GE Teach, a site developed by 9th-grade geography teacher Josh Williams, received a Geographic Excellence in Media Award in 2012. The site, until now, has been making excellent use of the Google Earth plugin to show side by side comparison views of various maps.

However, the site is now transitioning to a new version based on Google Maps. Despite the lack of 3D, it still looks good and has a number of notable features, including drawing tools, access to Google Maps Gallery, and Street View.

GE Teach Google Maps version


YoubeQ is a cross between a social network and a driving/flying simulator. It allows you to drive or fly a large number of different vehicles/aircraft around the globe while socializing with other people you meet on the way. When we featured it in June 2014, it had 13 vehicles and 3 languages. Until recently it was based on the Google Earth plugin. It has now been completely redone in WebGL using Cesium. Read more about it here. It now uses Bing Maps for the 3D portion and Google Maps for navigation.

The new YoubeQ, using Cesium and Bing Maps.

The post Google Earth plugin gradually fading away appeared first on Google Earth Blog.

Catégories: Sites Anglophones

USGS 3D Elevation Program

jeu 16-10-2014

The US Geological Survey (USGS) has a program called the 3D Elevation Program (3DEP).

From the USGS website:

The 3D Elevation Program (3DEP) initiative is being developed to respond to growing needs for high-quality topographic data and for a wide range of other three-dimensional representations of the Nation’s natural and constructed features. The primary goal of 3DEP is to systematically collect enhanced elevation data in the form of high-quality light detection and ranging (lidar) data over the conterminous United States, Hawaii, and the U.S. territories, with data acquired over an 8-year period. Interferometric synthetic aperture radar (ifsar) data will be collected over Alaska, where cloud cover and remote locations preclude the use of lidar over much of the State.

We believe that once completed the data will be placed in the public domain, which will mean that Google will use it in Google Earth. It is not clear how the resolution will compare to the 3D imagery that Google has been rolling out for cities that is created using a different technique. It would certainly not replace Google’s 3D imagery, as that requires not just a 3D model, but also photos of the different faces of the models, which will not be provided by the USGS data. However, it would certainly significantly improve the 3D landscape for areas where Google has not created 3D mesh.

Google has worked closely with USGS in the past. The Earthquake layer in Google Earth is provided by the USGS, as was the imagery used in Google Earth Engine to create global yearly images and a timelapse of the whole earth.

High-resolution lidar image of Mount St. Helens, Washington. Courtesy of USGS. A downloadable high resolution poster of this image can be found here

This article in the Washington post shows a sample of the new terrain maps, which clearly shows trees and is reminiscent of Google’s 3D imagery. However, this article from The American Surveyor shows a sample in which the trees hardly seem to feature. I guess we will have to wait for the first actual releases of data to see what the results are.

The post USGS 3D Elevation Program appeared first on Google Earth Blog.

Catégories: Sites Anglophones

Magnetic North and True North

mer 15-10-2014

A magnetic compass, including the compasses on most smart phones, does not point to the North Pole, or even to the North Magnetic Pole. Instead, it points away from True North by an angle known as the Magnetic Declination, which varies considerably, depending on where you are on the earths surface. It also varies slowly over time, as you can see in the animation on the Wikipedia page. On paper maps, this may be further complicated by a third direction known as Grid North, which refers to the direction northwards along the grid lines of the map.

We mentioned in this post a time animation for Google Earth, visualizing the Earth’s magnetic fields changing over time. You can check it out, but we had difficulty getting it to work well as an animation in the current version of Google Earth, although viewing an individual year is not a problem.

To find out what the magnetic declination in your location is, the US National Oceanic and Atmospheric Administration (NOAA), provides a handy tool on their website. There is also this useful site that lets you pick your loction on a map and tells you the magnetic declination. The ruler tool in Google Earth shows ‘heading’, so once you know your magnetic declination it is pretty easy to work out which way your compass will point in Google Earth.

Magnetic declination for Cape Town.

From what we can tell, the mobile versions of both Google Maps and Google Earth automatically correct for magnetic declination and always show True North, although we couldn’t find any documentation to that effect.

The post Magnetic North and True North appeared first on Google Earth Blog.

Catégories: Sites Anglophones

News Roundup: Polar ice caps, poachers and space detectives

mar 14-10-2014
Polar ice caps

The US National Snow & Ice Data Center (NSIDC) has recently updated their KML files of Arctic and Antarctic ice to include 2014 data. We have looked at their work many times in the past, as you can see here. Also of note is this press release from them explaining that the Arctic sea ice extent is shrinking and the Antarctic sea ice extent is growing. They also indicate this is the 6th lowest amount of ice recorded since they began measurements. Keep in mind that this is minimum and maximum extent of sea ice as measured by satellite and not thickness or total volume.

What interested me most about the animations showing the historical record is how the maximum extent of sea ice seems to be a very different shape each year.

Arctic sea ice extent, September 2014. The pink line is the monthly median sea ice extent 1981-2010

Poachers tracked down with Google Earth

There was an interesting story on about how a poachers’ camp was identified using the imagery in Google Earth.

The ‘machamba’ (small farm with a few huts) shown in the article.

The interesting part of the story from a Google Earth perspective is that the imagery used was from July 2013 and July 2012, yet it was still useful in tracking down active poachers in 2014. To see the location in Google Earth download this KML

World’s first space detective agency launched.

See the full article here.

Because satellite imagery is being used in court cases more and more frequently, Raymond Harris and Raymond Purdy have launched the world’s first space detective agency. They will specialize in finding and obtaining appropriate satellite imagery for legal cases as well as ensuring that the acquisition and subsequent handling of imagery meets the standards required by courts.

The post News Roundup: Polar ice caps, poachers and space detectives appeared first on Google Earth Blog.

Catégories: Sites Anglophones

The Napa earthquake in satellite imagery

lun 13-10-2014

We recently came across this map in the Maps Gallery which alerted us to the the fact that Google Earth (and Maps) has imagery taken soon after the magnitude 6.0 earthquake that struck Napa Valley, California in August. To find out when and where the earthquake took place, we can use the ‘Earthquake’ layer in Google Earth (found in the ‘Gallery’ layer). According to the marker on that layer, provided by the US Geological Survey (USGS), the Earthquake took place at 10:20:44 UTC on August 24, 2014, which was 3:20 a.m. local time. The latest imagery in the region is dated August 24, 2014, and judging from the shadows, was taken in the early afternoon. The whole area has the new 3D imagery, which is created with aerial photography captured before the earthquake, so to see the imagery from 24th August, turn off the 3D buildings layer. You will also not see the imagery in Google Maps, because it also shows the 3D imagery and has no way to turn it off or view historical imagery.

Although hundreds of buildings were damaged, very few collapsed, so in most cases the damage is not visible in the satellite imagery.

The map we referred to above highlights one of the buildings that partially collapsed during the quake, as seen in this news article.

An earthquake damaged building showing debris in the road and a crowd of onlookers.

Four homes burnt down in fire in mobile home park. See this news article.

Collapsed car port roofs. See news article here.

Water on road from ruptured water pipes.

Download this KML file to view the locations in Google Earth.

For our many other posts about earthquakes and the tools in Google Earth relating to earthquakes you can go here.

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