As a part of the Global Base Map plan, an easier way to start to work with satellite imagery and services provided by VANE platform, we have added low resolution imagery from Aqua and Terra satellites (aka MODIS). This kind of imagery enables Earth observation on a daily and hourly time basis and can be vividly combined with weather layers (previously we’ve posted about this part of the work on our blog). The delay between satellite overpasses and publication of the imagery is about 2 hours, this is the minimum time delay for Web Mercator version of this kind of satellite imagery, yet we look forward to reducing this time. About every 30 minutes new imagery comes from each of satellites.
Personally, I’m a big fan of NASA GIBS MODIS — where one can browse and download nearly all the products that can be generated based on MODIS imagery. But those who use this service as a real-time API, as I did, know the issue with the time delay and transparency (due to synchronization issue of the “no-data” layer). That’s why we decided to process low level data for Global Base Map.
In the sample image below showing the comparison of VANE and NASA GIBS layers as for Terra satellite, the divider’s bar defines the time difference between one and the other, which is about 3–4 satellite passes for mercator projection and 1–2 for latlon which is the default projection for Worldview. Also there is some issue to use GIBS layer with a transparent background to overlay it on base maps. You can check this example live at http://owm.io/cases/test-modis and you can get the both of the layers at http://owm.io/modis
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THE COMPARISON OF VANE AND NASA GIBS LAYERS AS FOR TERRA SATELLITE IN WEB-MERCATOR PROJECTION
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Next step we are going to bind this layers in one single mosaic to add it to “Weathermap” application where it can be combined with weather layers and to provide it through VANE API for everyone. (Stay tuned to know about “Open Satellite map” that’s coming pretty soon.)
To start using these maps from third-party applications and to get tiles from server you have to generate an API key under your personal Openweathermap account — thus users can use it in a vast range of clients from GIS desktops to web-mapping libraries (see more detailed description and examples). You can sign in under your Openweathermap account or create a new one.
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OPERATIVE TERRA IMAGERY FOR THE CURRENT DATE (13 MARCH) COMBINED WITH PRECIPITATION LAYER — BOTH LAYERS ARE GENERATED ON THE TOP OF VANE PLATFORM
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