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The Lodos winds and the Sahara

Dust from the Sahara Desert sweeps over the Mediterranean sea and into Turkey.

On February 1st 2015 Western Turkey and Greece experienced something quiet surreal, a strong south-westerly wind that was so strong that it produced large waves, damaged buildings and had many flights grounded in both countries. This wind which the local Turks call Lodos, literary meaning “southern wind” is a common occurrence and can happen as many as twenty times a year, sometimes with debilitating results.

Although it produces a great deal of turbulent waters in the Mediterranean and even in parts of the Black Sea it on occasion picks up dust from the Sahara desert in Africa. This dust is often carried as far north as Southern Ukraine and is very mineral rich. Although the minerals have been stated to be very beneficial to plant life in the area, prolonged exposure to humans can cause headaches, bronchitis and other respiratory diseases. At its hight the dust cloud can cripple urban centres as visibility drops to near blinding and all major transport is halted, this includes planes, trains, cars and even sea vessels. At times the Bosphorus Strait is even closed off till the winds and dust subside.

The below images captured by the MODIS instrument on board the Aqua satellite showing the extent of the dust stretching across the Mediterranean Sea and over Greece and Turkey.

The dust cloud can be clearly seen here over the Mediterranean Sea. Image courtesy of NASA.

 

The dust cloud highlighted in shades of orange. Image courtesy of NASA.

More images of the event can be seen on NASA’s Worldview website here.

If you would like to know more about Scantherma’s remote sensing services you can drop by our Perth office where one of our technicians will be glad to assist, or alternatively you can visit the remote sensing section of our website here.

The search for Malaysian Airlines Flight MH370; an image engineering approach

Scantherma will be holding a presentation for Engineers Australia to showcase its methods using different image engineering to assist with the search for Malaysian Airlines Flight MH370. The presentation will be held at the Engineers Australia WA Division in West Perth. Details to follow:

Abstract

On the 8th of March 2014, Malaysian Flight MH370 disappeared. What followed was an un-precedent search effort involving over a dozen countries and a combined search area of over 1/10th of the Earth’s surface. At no time in modern aviation has there been such a myriad of facets in the use of technology in finding an aircraft. Scantherma was tasked  to use its “object-based image analysis” (OBIA) algorithms to comb through hundreds of satellite images containing potential wreckage in the southern Indian Ocean. This proved to be a new approach in utilising image engineering to a totally different audience. After more than 3 weeks of analysis, the search using satellite imagery was abandoned. However, the exercise proved extremely useful in not only identifying new OBIA methods; but also its application towards oceanic remote sensing in general.

Image showing velocity of currents in the eastern Indian Ocean. Overlayed is the  search areas analysed by satellite imagery over 3 weeks in March and April, 2014. The input of current velocity and direction was crucial in setting up algorithms for the use of OBIA. [Source: Scantherma 2014]

Image showing velocity of currents in the eastern Indian Ocean. Overlayed is the search areas analysed by satellite imagery over 3 weeks in March and April, 2014. The input of current velocity and direction was crucial in setting up algorithms for the use of OBIA. [Source: Scantherma 2014]

Software Used
  • Trimble eCognition
  • Mappt
  • ER Mapper
  • QGIS
Acknowledgements
  • Christian Hoffmann (Trimble)
  • Trevor Marshall
  • Michael Breen
  • JJ Rodrigues

Perth remote sensing firm on MH370 mission

By Liam Croy [Story as it appeared in The West Australian – 3rd of April, 2014]

A Perth remote sensing company has been tasked with finding the wreckage of MH370. Welshpool-based Scantherma applies its mapping and imaging technologies across a range of residential, commercial, agricultural and resources projects. From iron ore exploration in the jungles of West Africa to energy efficient homes in Perth, Scantherma’s capabilities are diverse in nature and scale.

Chief executive Amir Farhand and his 11 staff do the bulk of their work in the resources industry, where they have teamed with BHP Billiton, Fortescue Metals Group and the world’s largest iron ore producer, Brazilian corporation, Vale.

They are currently working with Samsung C&T on the Roy Hill project in the Pilbara. But after a “serendipitous” meeting at a recent mining expo in Hong Kong, Scantherma took on its biggest and most unique challenge yet.

“We were contacted by a very large insurance company which might have a big bailout because of this missing plane,” he said.

The Perth company was commissioned to use its “object-based image analysis” software to comb through hundreds of satellite images containing potential wreckage. They analysed 437 images of debris in the original southern Indian Ocean search area, before shifting their focus north-east last Wednesday based on ocean current data. Two days later, the Australian Maritime Safety Authority announced a new 319,000sq km search area in the same region.

“There was plenty of debris in those first 437 images but it wasn’t from the plane,” he said. “It was mostly white caps and sea junk. Global shipping lanes pass through that area to the south of Western Australia.

“What (AMSA) is doing is terrific because they’ve only got finite resources. Our stuff is done on computer but it takes four hours just for the planes to get out there.

“It’s just such a vast area. We’re in mining so we say it’s like trying to find Lasseter’s Reef.”

Mr Farhand said the insurance company was expected to call off the search this weekend when the plane’s black box was due to run out of battery. But for now, four US and Japanese satellites are scanning a search area nearly four times larger than AMSA’s site.

He said Scantherma’s chief remote sensing analyst was stationed in Florianopolis, Brazil, ready to identify any signs of MH370 in the next set of images.

“It’s been incredible. Most of the work we do is for mining companies, so it’s been terrific to be able to use this technology for a humanitarian purpose,” he said. “As a society, I think we need to embrace these types of technologies more.”

Original Article

Loading Tiled Imagery into Mappt

Last week I posted an article about Mappt supporting Compact Cache Bundles but did you know it already supports tiled imagery.  The difference between the two is that tiled imagery is exploded so each tile is it’s own image file.  There are three bit’s of information a tile needs to display on a google map.

  • The Level of Detail (LOD)
  • X position and
  • Y position

Tiling programs generally create a directory hierarchy to define these three properties.

Directory tile hierachy

Here the first directory is the LOD.  The next is the X location and the filename is the Y.   This is the most common structure but occasionally you will come across tiles with a single filename that contains the LOD, X and Y separated by an underscore character:

tile_hierachy_small

Mappt is capable of using both of these tiled images formats.  Just transfer the tiles to the tablet via the USB cable and make note of where they are located.   Personally, I load them into the Mappt -> Downloads folder and use ER File Explorer to  verify the exact path to the tiles.

es_file_explorer_path

Now select ‘Tiled Map Layer’ from the ‘Add/Load layer dialog’.

select_tiled_map_layer

Enter a name for the new layer and then type in the path to the tiles.

add_tiled_map_layer

The important part here is the fields surrounded by the curly brackets ‘{zoom}/{x}/{y}.png’ .  This part defines the structure of the tiles as discussed above.

Mappt now supports ArcGIS Compact Cache Bundles

We are pleased to announce that Mappt now supports ArcGIS Compact Cache Bundles.

Loading in your own satellite imagery is a common feature request for Mappt  and it’s not hard to see why.  Accessing your own imagery from a tablet gives GIS professionals and field workers the unprecedented power of being able to stand inside their data and perform ground surveys and analysis with total confidence they are looking at the correct features.  The inclusion of Compact Cache bundles is one of several new features that allows loading of custom imagery into Mappt and at the time of writing we are the only option outside of ESRI to utilize this format.  Mappt has been tested on the Sony XPeria Z with 30Gb of imagery and we have found the only limitation is the amount of free space on the SD card.

Mappt with a Compact Cache Bundle of ASTER satellite imagery.

Mappt with a Compact Cache Bundle of ASTER satellite imagery.

Compact Cache Bundles are a convenient format for tiled Imagery.   The biggest advantage of compact caches over an exploded format is that it eliminates the overhead associated with thousands of little files which means faster file transfer times and less space on disk.  This is a huge deal when transferring several Gigabytes worth of imagery onto a tablet.

Behind the scenes compact cache bundles act like a phone book.

compact_cache_bundle_hieracy

Up to 16,000 tiles for a particular level of detail are conglomerated into a single file with a .bundle extension.  This file has a companion with a .bundlx extension that acts like an address book for tiles.   Looking up the address for a tile has some computational overhead compared to an exploded format but fortunately we were able to optimize it to the point where there is no impact on Mappt’s performance.

Australia’s Great Barrier Reef in 3D

Researchers at EOMAP, a German aquatic remote sensing company, have for the first time created a 3D digital map of the Great Barrier Reef.

The Great Barrier Reef is the world’s largest coral reef ecosystem covering an area close to 350,000 square kilometers. EOMAP used satellite imagery and state of the art software to map this natural world wonder in 3D, giving a much more detailed image than what was previously available. In the past scientists had surveyed the Great Barrier Reef using more conventional methods such as boats and sonar but this new method has outputted an image of the Reef at a resolution never before seen at a depth of 30 meters.

Scantherma eomap great barrier reef image3

Image courtesy of EOMAP

Scantherma eomap great barrier reef image1

Image courtesy of EOMAP

Scantherma eomap great barrier reef image2

Image courtesy of EOMAP

 

Dr Robin Beaman, a marine geologist at James Cook University in Cairns says the data could provide policy makers and researchers with vital information needed to combat threats to the reef. This includes measuring the impact of rising sea levels and helping to measure water quality and ocean currents. It could also be used to model crown of thorn starfish larval trajectories to determine where they are next likely to inhabit the Great Barrier Reef.

 

Scantherma Great Barrier Reef 500m

3D file of the Great Barrier Reef at 500 meters resolution. This file is downloadable in full from the EOMAP website.

 

Scantherma Great Barrier Reef 2m 2

A sample area of the Great Barrier Reef 3D file at 2 meters resolution. This data can be purchased from the EOMAP website.

 

Scantherma Great Barrier Reef 2m

The same 2 meter resolution sample area as above from a different angle. Great detail can be seen here in the blue area (reef).

 

For interested parties the imagery is available for purchase at EOMAP’s website with small sample areas available for free download.

 

For more information visit

EOMAP: http://www.eomap.com/great-barrier-reef

Dr Robin Beaman:    http://www.deepreef.org

Great Barrier Reef Marine Park Authority: http://www.gbrmpa.gov.au

Scantherma’s Remote Sensing services here.