My Google Map Blog

Our first YouTube video where we explore Google Maps Street View in Mexico has just been released. Any suggestions on themes for future videos?

Yesterday Google surprised us by adding global mosaics created from Landsat and Sentinel 2 data to the Google Earth’s ‘historical imagery’. The data comes to Google Earth via Google Earth Engine, which has long had this time-lapse feature that has just been updated to include imagery up to 2016. The timelapse page also tells us more about the imagery:

Using Earth Engine, we combined over 5 million satellite images acquired over the past three decades by 5 different satellites. The majority of the images come from Landsat, a joint USGS/NASA Earth observation program that has observed the Earth since the 1970s. For 2015 and 2016, we combined Landsat 8 imagery with imagery from Sentinel-2A, part of the European Commission and European Space Agency’s Copernicus Earth observation program.”

Google Earth Engine has also published this post about the update.

On Friday we will release a KML file that will allow you to view similar time-lapses from directly within Google Earth.

Today we are making a few observations about the imagery.

The first observation comes from GEB reader ‘haflaa’ who points out that although the mosaics are global for every year between 1985 and 2016, there are some locations, such as the Maldives, where the imagery is identical for a number of years. In the case of the Maldives, the imagery is identical from 1985 to 1999.

We also note that the Google Earth Engine animation starts in 1984, whereas the Google Earth data starts with December 1985 (which we presume represents the data for the whole of 1985).

The path of the satellite is often noticeable in the imagery. For more on the orbit of the Landsat satellites see this post and this post.

In many locations you will notice narrow stripes in the imagery. This is because of a faulty part on the Landsat 7 satellite. Learn more about it in this post.

The mosaics are created by trying to select imagery from throughout a given year then selecting cloud and snow free pixels where possible. However, there are a few locations on earth that are almost always cloudy, a problem we discussed in this post.

This location in Cameroon features both Landsat 7 stripes and clouds that just could not be eliminated.

The post More about the new Landsat / Sentinel 2 data in Google Earth appeared first on Google Earth Blog.

Larger (thanks Ricardo)

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Thank you for GEB reader Jonah for being the first to let us know. Google has added yearly global mosaics using Landsat and Sentinel 2 data going back to 1985. Google has long had these mosaics on Google Earth Engine which also provides a ‘Timelapse’ tool. As of this writing, the Google Earth Engine timelapse only goes up to 2012, but that will likely be updated too.

To see the mosaics, simply zoom out a bit and switch to ‘historical imagery’.

We plan to create tools to animate the new data, but that may take a few days.

Here are a few ‘before and afters’ showing changes between 1985 and 2016.

The Amazon, 1985 vs 2016

Dubai, 1985 vs 2016

The region around Shenzhen, China, 1985 vs 2016

Note that the new data is created by blending all Landsat/Sentinel 2 data for a whole year to remove clouds and snow cover. The result is that changes that happen on timescales less than a year, such as seasonal changes, will not be visible.

Google has not (as of this writing) updated the historical imagery layer with all the high resolution imagery that has been added since June 2016.

There is one disadvantage to the new data – it is much harder to find historical imagery, as you need to zoom in very close to the earth to see the high resolution historical imagery.

The post Google Earth now has global Landsat and Sentinel 2 data from 1985 to 2016 appeared first on Google Earth Blog.

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We recently came across Italian artist Dario Gambarin who has been creating a large amount of land art in fields near the Italian town of Castagnaro. He creates his art in actively cultivated fields, so it typically does not last long. As a result, only a few of his works can be found in Google Earth imagery.

“No Inceneritore” – objecting to an incinerator being built in the region.

“Italia in Campo” (Italy in the field). Portrait of Italian football player Mario Balotelli featuring his mohawk hairstyle as seen from the back.

“In ricordo di Crevalcore” (In memory of Crevalcore). In memory of the 2012 Italian earthquake

“Benedictus XVI” A dove for the pope.

We found what appears to be the artist’s website, but it only shows his early works. A Google image search reveals a lot more artworks, including some that are particularly relevant to current news, including a portrait of Fidel Castro, who recently passed away, and a portrait of Donald Trump with the word ‘Ciao’ (bye) apparently created when it looked like Clinton would win the US election.

We were able to find the locations of most of Dario’s works listed on his website and have put together this KML file showing that he mostly uses the same seven fields again and again. There were a few that we failed to locate, so there may actually be more of his art in Google Earth imagery that we did not find.

The post The land art of Dario Gambarin appeared first on Google Earth Blog.

Larger (thanks Mr Jackie)

Larger (thanks Gilbert)

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