July 29th, 10:14am 0 comments

Whitebark pine tree faces extinction threat, agency says - The Washington Post

Media_httpwwwwashingt_idabo

[I posted this a week ago but Amplify didn't autopost it to Posterous. So I'm reposting].

The Fish and Wildlife Service determined Monday that whitebark pine, a tree found atop mountains across the American West, faces an “imminent” risk of extinction because of factors including climate change.

The Post also reports that the FWS can't list the species in the Endangered Species List because it could not afford it. The House Appropriations Committee has eliminated funds for ESA listing from the budget.

File under "decline and fall".

Posted
April 3rd, 4:07am 0 comments

Heat Stress Could Make Parts of the Planet Uninhabitable

I learned this week that according to some plausible scenarios, that half the inhabitable Earth could become uninhabitable in 300 years.  A sometimes overlooked aspect of climate change is the potential for heat stress on humans and other living things.  According to a new report*, heat stress imposes an "upper limit to adaptation", one that we will reach under some scenarios.  Temperatures in excess of 35 degrees Celsius induce hyperthermia in mammals. "While this never happens now, it would begin to occur with global-mean warming of about 7 °C, calling the habitability of some regions into question. With 11–12 °C warming, such regions would spread to encompass the majority of the human population as currently distributed. Eventual warmings of 12 °C are possible from fossil fuel burning. One implication is that recent estimates of the costs of unmitigated climate change are too low unless the range of possible warming can somehow be narrowed....a global-mean warming of roughly 7 °C would create small zones where metabolic heat dissipation would for the first time become impossible, calling into question their suitability for human habitation. A warming of 11–12 °C would expand these zones to encompass most of today’s human population.'

Of course when we all run to the other side of the boat we will encounter another tipping point.  

A number of questions arise relating to freedom and responsibility that will need to be addressed soon.  Left unchecked, could climate change mark the end of the American experiment with liberty?  At a minimum humanity  may be challenged to reframe ideas about liberty and progress.  

*Stephen Sherwood and Matthew Huber, writing in the online edition of the Proceedings of the National Academy of Science (http://www.pnas.org/content/107/21/9552.full?sid=d38fdf62-80df-4419-9ca7-01773e9a0827)

Posted
February 16th, 7:51am 0 comments

An island consumed by invasive vines

(download)

images copyright Benjamin White and Google Earth, all rights reserved

Over the past year, I’ve been working with a Cook Islands NGO, Te Rito Enua, with funding from the Asian Development Bank, to develop a pilot project on participatory GIS as a tool to assist island communities to develop climate adaptation strategies. While there, Mona Matepi, president of TRE, called my attention to the problem of invasive vines on the island of Rarotonga. Three species of woody vines* are colonizing the island forests, causing massive deforestation. The overtop and kill trees, replacing the forest with a solid jungle of vines.  Since Rarotonga is dependent upon surface water for its entire supply, and since vines were killing the trees in its forested watershed, it seems like a non-trivial issue.  Nobody knows how the vines will affect water supply.  Will they reduce surface water supply through evapotranspiration?  Will they hold the soils as well as the trees they are replacing?  How will they respond to the more frequent cyclones and droughts that climate models predict?  And, if they are a problem, how can they be controlled?  Many questions to answer - our challenge right now is to find support for research into the issues and the options available.  If no one does anything, there’s a chance, and its not a tiny one, that there could someday be a humanitarian crisis that would have severe implications for one of the dwindling number of robust Polynesian cultures remaining.  

I asked University of Maryland doctoral candidate Benjamin White, a remote sensing specialist, for advice on how to illustrate the extent of the vine infestation.  The island is rugged and steep, difficult to map on foot.  But I was able to take some measurements using a handheld GPS unit.  Ben offered to have a go at classifying the vines using my field observations as training data.  Commercial remote sensing imagery provider GeoEye donated high-resolution (4m and 1m) satellite images. Ben developed a sophisticated neural net classifier, and processed the images as R/G/IR reflectance, reflectance-based NDVI, principal components, mean texture and a quick reflectance to “dense vegetation” classification.   The final result was uploaded to Google Earth for visualization purposes; Google Earth data is not useful for this kind of application, but overlaying the classification results on a Google Earth image (Figure 3) gives a context in terms of location and topography.  Additional satellite imagery could provide complete ground coverage and (subject to availability) time series to measure change in land cover.  

I’m hoping that the image will drive home how bad the problem is, and mobilize some support for Te Rito Enua and the Cook Islands government to get a handle on the vine problem.

Heartfelt thanks go to Ben White and the University of Maryland Geography Department, GeoEye, and the Asian Development Bank for support.

* the vines are Cardiospermum grandiflorum, Mikania micrantha, and Merremia peltata. 

 

Posted