Thursday, August 18, 2005

Climate change, global and regional

At the Portland Peak Oil meeting last night, we had a presenter from Portland's Office of Sustainable Development walk us through calculating our baseline of energy use and CO2 emissions. In the process, he happened to mention expected changes to our regional (Pacific Northwest) climate, as researched by the University of Washington's Climate Impacts Group:

  • Amount of rainfall the same, but coming in short intense storms rather than drawn out
  • Summer dry spell will extend one month in each direction, for an extra two months total of drought
  • Spring will continue to come earlier and earlier each year
  • We'll see more days in the summer with intense heat, such as over 100 degrees Fahrenheit
  • No snow in winters

It struck me that I dropped the ball big-time in designing Theressa's yard (and to some extent Leah's) without fully researching where our climate is likely to be headed. In the future I'll be paying more attention to plants that are drought tolerant and worrying less about cold hardiness, and focusing more on cooling houses in the summer rather than maximizing heat gain in the winter. Water catchment also becomes even more important.

Anyone preparing for the future challenges we're facing should find solid information on local climate change predictions and also try to figure out social implications. (Here we're very concerned about millions of Californians and other Southwesterners crowding into the Pacific Northwest). On the east coast for example, you'll want to pay really close attention to the possibility of the conveyer belt shutting down, staying up to date on the latest scientific predictions of how likely it is, and how much warning you might have if it begins (5 years? 1 year?)

Some troubling recent news on the global climate change front:

  1. Scientists have just discovered that an area of permafrost in Siberia the size of France and Germany combined is beginning to melt. Bottled up underneath the frozen peat bog is billions of tons of methane, which is 20x as powerful a greenhouse gas as CO2. This is potentially the tipping point of runaway global climate change, a point of no return, as the melting permafrost releases methane which increases the temperature which accelerates the melting and on into the positive feedback loop. It may already be too late to stop catastrophic climate change, and with this news it looks like if we do have any remaining window of opportunity it's closing faster than ever.
  2. The Amazon rainforest may be reaching a tipping point of its own, as its destruction has altered local climate patterns enough that the rainforest may start dying off on its own, even without active human destruction. In the bigger picture this is potentially another runaway global climate change trigger point, as the CO2 sequestered by the rainforest dwarfs our annual emissions. If the rainforest begins to self destruct, releasing more CO2 which increases climate problems which accelerate the rainforest's destruction, off we go again on the positive feedback loop. Presumably massive efforts to reforest the area (especially with the help of permaculture concepts) could stave off such a runaway process, but I'm not holding my breath on the western world ceasing its exploitation of the forests, let alone providing the resources needed to turn this situation around.

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