Climate change is rearranging the global landscape, threatening to wipe out 20 to 30 per cent all the life forms on earth and flood hundreds of millions people out of their homes, according to the authors of an international report to be released Friday.
Their draft report, obtained by CanWest News, says Canada will face big problems as temperatures rise - twice as many forest fires, vast tracks of melting permafrost, deadly heat waves - but they pale beside the grim forecast for the world's poorer countries and citizens.
"Hundreds of millions of people are vulnerable to flooding due to sea-level rise," says the report. By 2100, it says rising waters will drown low-lying, and densely populated coastal regions in Asia and small island countries.
It says one sixth of the world's people also face growing freshwater shortages as snow-packs shrink and glaciers recede.
Ecosystems and their inhabitants - mangroves, coral reefs, salmon runs, polar bears - are also at risk, the report says: "Roughly 20-30 per cent of species are likely to be at high risk of irreversible extinction if global average temperature exceeds 1.5-2.5 C," which could occur within decades given current greenhouse gas levels. It says many more plants, bugs, birds and mammals could disappear if temperatures climb much beyond that.
Delegates from Canada and more than 120 other countries are meeting in Brussels this week to finalize and approve the report to be released Friday. It is the second of four studies to be released this year by the Intergovernmental Panel on Climate Change, a United Nations network of close to 2,000 scientists. They assess available evidence to produce "consensus" reports on climate change and what should be done about it.
The first report, released in February, said global warming is "unequivocal" and human activities, such as the burning of fossil fuels, is the main driver causing temperatures to climb. That report prompted Canadian Prime Minister Stephen Harper and other leaders to promise to cut greenhouse gas emissions associated with the rising temperatures. Friday's report will put more pressure on governments to cut emissions and launch programs to try adapt.
The scientists say change is already clearly underway: "Many natural systems, on all continents and in some oceans, are being affected by regional climate changes, particularly temperature increases," says the final draft of the scientists 21-page summary-for-policymakers.
Melting glaciers and unstable permafrost, earlier spring runoff and bird migrations are now evident, the scientists say. But they say this is just the start of much bigger and irrevocable changes to come.
The report says there will be some benefits - more shipping through the Arctic, fewer people freezing outside in the winter, and Canadian farms and forests expanding northward.
But the list of negatives is much longer - millions more people will go hungry as droughts and crop failure worsen, billions of people will face drinking water shortages and, by the end of this century, hundreds of millions of people in "mega-deltas" in Asia and on small islands could be inundated by oceans that are rising as temperatures climb and ancient ice sheets melt.
Climate change could eliminate up to 30 per cent of life forms
Margaret Munro, CanWest News Service
The scientists note sea level rise is not something that can be turned off like a car engine.
"Sea level rise has substantial inertia compared to other climate change factors and is virtually certain to continue beyond 2100 for many centuries," they note in the final draft of their 79-page technical summary also obtained by CanWest News. "Stabilization of climate could reduce but not stop sea level rise."
The summary report predicts malnutrition and disease, particularly in Africa, Latin America and some Asian countries, will increase along with crop failures, droughts and floods that are expected to grow more severe in coming decades.
Heat waves are also expected to become more intense and deadly in North American and European cities. One scenario predicts ozone-related deaths, associated with smog and heat waves, will climb almost five per cent in North America by 2050.
Fresh water will become scarcer as glaciers and snow-packs disappear. If current warming rates continue, the report says Himalayan glaciers that supply freshwater to millions of people could shrink from 500,000 square kilometres today to 100,000 square kilometres by the 2030s. Shrinking glaciers and snow-pack in Western North America and lower water levels in the Great Lakes are also looming problems for both water security and relations between Canada and the U.S., the report says.
Fire, pests and disease are also forecast to cut a much wider swath through Canadian forests, with the amount of forest area burned each year expected to almost double by 2100.
The Arctic will experience remarkable change with "both negative and positive impacts" for people in the North, the report says.
Less summer sea ice will open up polar shipping, but will also increase frequency and severity of coastal erosion and storms hitting low-lying coastal communities. There will also be "detrimental effects" on polar bears, seals and migratory birds.
Rising temperatures will also lower barriers to species invasions. Lyme disease is forecast to move 1,000 kilometres north by 2080 along with a two- to four-fold increase in ticks, which can infect both wildlife and humans with encephalitis.
The Arctic landscape is already being transformed as tundra gives way to forests and permafrost melts turning winter roads and building foundations to mush. The reports says by 2050 up to 35 per cent of the permafrost in the Northern Hemisphere could be gone.
Ecosystems in the tropics will also be radically altered as tropical forests are stressed by the heat and coral reefs are bleached by warmer, more acidic oceans.
"The resilience of many ecosystems is likely to be exceeded this century by an unprecedented combination of climate change, associated disturbances (e.g., wildfire, insects), and other global change drivers," says the report.
Among the 20-30 per cent of species at risk of vanishing if temperatures rise just 2.5 C are 30 Amazonian trees and several mammals, birds, butterflies, frogs and reptiles. If the temperatures rise 4 C the report predicts there could be "major extinctions around the world" of about 40 to 70 per cent of known species. Hundreds of millions more people would also face water shortages and starvation, the report says.
http://www.canada.com/globaltv/ontario/story.html?id=0865f445-31a4-4ff5-8875-c6a9651b1c30&k=31613
20-30% of the species disappearing due the wiping out of their habitats from flooding, climate change, and extreme temperatures that are not regular and animals cannot adapt to. The saddening thing about this article is that we have to be the ones to assist this in not occurring (as rapidly) as we were the destroyers that did this to them in the first place.
Wednesday, April 4, 2007
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