Ecology from the Air – Greg Asner (2009) TED Talk

Being able to measure interaction of the living and the non-living at large continental-scales is eye opening. That’s what successful scientist Greg Asner does with the Carnegie Airborne Observatory (CAO).

NASA’s Landsat earth observation satellites have been feeding us invaluable global-scale data for more than 40 years. The new satellite Landsat 8 began transmitting near-realtime information. Thanks to these earth observation satellites we can instantly know scale of natural or human-made impacts on ecosystems. Deforestation for oil palm plantations in Peru or fragmentation of last continuous natural areas by a highway construction bisecting northern forests of Istanbul can all be seen in time series. Even rare once in a few century events like the Chelyabinsk meteorite airburst can be tracked with great accuracy.

We can see changes in very large scales from space. Similarly at very local small scale it is possible to capture details of objects from the ground even with a photographic camera. The video of a tree stump below was produced from overlapping pictures taken by a handheld camera. Computer algorithms can process and stitch images to build a complete three dimensional model.

Tree Fall Modelling 02 from Uzay Sezen on Vimeo.

At intermediate landscape scales we were lacking affordable high-resolution monitoring and that’s what CAO does. Ability to resolve a continuous forest canopy structure of a dense tropical forest and even identify individual tree species is very powerful. Measuring growth and carbon storage capacity of a forest can help us understand and predict climate altering atmospheric gasses such as carbon dioxide and methane. “How do we manage our carbon reserves in tropical forests?” is an extremely relevant question to solve the most important crisis humanity has created. Atmospheric carbon dioxide concentrations are soaring. In May 2013 levels passed 400 ppm reaching a concentration not seen on the earth for millions of years.

A vast proportion of atmospheric carbon dissolves in the oceans. Since the industrial revolution worlds oceans became 30 percent more acidic. Tracking movement of carbon in gas form is useful to understand distribution of heat trapping gasses and aerosol particals. Among these soot also known as black carbon enters the air when fossil and biofuels are burned and can affect Earth’s climate on a regional scale. The visualization below uses data from NASA’s GEOS5 climate model to show black carbon’s atmospheric concentration over Indian subcontinent from August to November in 2009.

Black Carbon Movement in the Atmosphere NASA from Nature Documentaries on Vimeo.

In a warming world plants have two options to adapt and survive. One option is to migrate towards cooler northern latitudes. Another is to move into higher ground. Mountain systems like the Andes are very important in this respect. A study based on historical vegetation surveys in west Europe has shown that global warming trend is too fast for plants to catch up especially for tree species. There is now a concept known as the “climate speed”. We urgently need rapid aerial surveys like that of CAO to get an accurate picture of vegetation dynamics in our fast changing world. This information will be crucial to calibrate future climate scenarios.



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