Connecting people: A world map of undersea cables

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Despite satellite technology, global communication heavily relies on undersea cables to keep people connected. “A submarine communications cable is a cable laid on the sea bed between land-based stations to carry telecommunication signals across stretches of ocean.” (Wikipedia) Undersea cables are the backbone of the internet, so that being connected determines a region’s ability to participate in global communication flows.
The following cartogram shows data from Greg’s Cable Map reprojected onto an equal population projection, giving a perspective of how people rather than land areas are connected to the global communications infrastructure. Landing points where the cables connect to land are marked as red dots in the map, while the background also shows very faded shipping lanes (over sea) as well as the gridded cartogram projection (over land):

Cartogram of undersea cables shown on an equal-population projection
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Water worlds: Ocean Chlorophyll levels

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The ocean is the last frontier that has not been discovered by cartogram techniques before. As such, it was an inevitable step in my PhD research some years ago to test the creation of a gridded ocean cartogram, a cartogram that is limited to the extent of the world’s oceans (also linking nicely to my past research on coastal ecosystems).
Chlorophyll concentrations in the world’s oceans are important indicators for the presence of algae and other plant-like organisms that carry out photosynthesis. As such, phytoplankton (which contains the chlorophyll) is an essential element of the food chain in the seas as it provides the food for numerous animals. Variations and changes in the chlorophyll levels are also relevant for the study of the ecology of the sea. Changing chlorophyll levels can indicate changing sea temperatures and other conditions in the oceans that cover about 72 percent of the planet’s surface.

Gridded cartogram visualisation of Ocean Chlorophyll concentrations
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Hyperspectral remote sensing and analysis of intertidal zones

The growing amount of remotely sensed data and the ongoing developments in the improvement of spatial and spectral resolutions lead to high expectations. These often inflated expectations are usually not fulfilled. I explored these expectations and aimed to make a contribution to bring them to a more accurate level in research in the field of hyperspectral image analysis of small scale and heterogeneous biotopes in the intertidal zones of coastal areas which I undertook back at my time at the University of Cologne and the Alfred Wegener Institute for Polar and Marine Research Bremerhaven. Here are some insights from my work.

Map overview of the Study Areas on Helgoland and Sylt
Overview of the study area on the islands of Helgoland and Sylt, Germany
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