Thank you to GEB reader Jonah for letting us know that Google appears to have quietly dropped the ‘radar’ layer from the weather layers. This is in addition to the “Conditions and Forecast” and “Ocean Observations” layers which were dropped last October, having been broken for quite some time.
Google has added a short comment to the announcement page for the previous layers on the Google Maps help forum:
Update (2017-01-18): We’ve also removed the “Radar” layer as our third-party data feed has broken as well.”
So all that is left in the weather layers now is the ‘Clouds’ layer.
We noticed this interesting triangle-shaped storm in the South Atlantic
The Google Earth weather layers “Conditions and Forecast” and “Ocean Observations” have been broken for some time. We did a post on it in July this year, but at that time it had already been broken for several months. Google has now announced that it will be dropping the layers from Google Earth on October 10th, 2016.
Dropping the layers is certainly better than leaving them broken in Google Earth, as there is currently no indication that they are not displaying the correct information. What do our readers think of this move? Was the layer useful to you? Would a KML file with similar functionality be useful? Let us know what you think in the comments.
The Google Earth “Conditions and Forecast” and “Ocean Observations” weather layers.
Over the last few weeks we have had several emails from GEB readers saying that the weather information in Google Earth is not accurate. We have compared the temperatures shown in Google Earth with those shown on weather.com, which is listed as the source of the information in the Google Earth popups, and we have found that the figures do not match and in some cases there are significant differences. Last year the weather layers had a similar problem, with the weather data simply not being updated. In that case it was obvious that the issue was a communication problem between Google Earth and the source of the information, as the dates shown in the popups were not being updated, indicating that the data was old. This time, however, the dates shown in the popups are current, but the actual figures are not changing. We checked some locations and although the date shown changes quite regularly the figures displayed in the popups do not. Only the ‘conditions and forecast’ layer is affected as far as we can tell. We verified by comparisons to various websites that the cloud and radar maps are reasonably current.
Despite the name, Snowville, Utah, is actually quite hot this time of year, yet Google Earth gives it 37°F / 3°C.
Weather.com gives its temperatures in the 55°F – 90°F range, so the issue is not one of time of day.
We checked locations on several different continents and the issue seems to be universal.
A GEB reader recently remarked that the Google Earth Clouds layer (a sub layer of the Weather layer) appears to have fewer clouds than it should when compared to the ‘Radar’ layer that often shows rain and storms in apparently cloud free areas.
The first thing to know about the Clouds layer is that it is not an optical photo of the clouds as they are seen from space. If we look at the images from a weather satellite such as Himawari 8, that we have looked at in the past, we can immediately see one of the problems that would arise from purely optical images. Approximately half the Earth is in darkness at any given time.
Left: Google Earth Cloud layer. Right: Image from Himawari weather satellite.
Weather satellites have a range of sensors that can detect clouds even in darkness. They make a map of the clouds that is then converted into an image with white where the clouds are that is then used in Google Earth. However, they appear to focus only on thick clouds, which results in an image showing a lot less clouds than can be seen in an typical photo from a weather satellite.
The Weather layer has an Information layer that includes the option to download animations of the Clouds and Radar layers. It also tells us that the data for the Clouds layer comes from the Naval Research Laboratory (NRL) Marine Meteorology Division. We had a look around their website but were unable to determine exactly which satellites are used for the Google Earth Cloud layer or anything about the process used. We think the data may come from MODIS (or Moderate Resolution Imaging Spectroradiometer) an instrument found on the Terra and Aqua NASA satellites. Learn more about them here. We also found this highly technical article about the algorithms used to collect cloud data and it is clearly a complicated process.
If any of our readers knows more about where the Google Earth Cloud layer comes from and how it is processed please let us know in the comments.
As a number of GEB readers have noted, some of Google Earth’s weather layers have not been working correctly and as of this writing the data is out of date. The ‘Conditions and Forecasts’ layer has not been updated since May 28th, 2015. The ‘Oceans Observations’ layer has even older data, mostly from 2013. The ‘Clouds’ and ‘Radar’ layers are up to date – see the ‘Information’ layer for exact date and time for each and for animated versions of both layers.
We believe Google is aware of the problem with the ‘Conditions and Forecasts’ layer and is working to resolve it. Because weather information is really only useful when it is current, Google should consider modifying the layer to either give a clear warning message when weather information is out of date, or to replace the old data altogether with a ‘data unavailable’ message.
It is, of course, possible to get weather information from many other sources including weather.com the source Google Earth uses. We have not been able to find any site that gives similar weather information in KML format, but there are a number of different weather resources that are available in that format. A while back Frank made a collection of weather resources and it was updated by Mickey. We have also found that NOAA and NASA provide a variety of weather datasets as KMLs, although they are mostly focused on North America.