A reader points out that the front page of MSN today has an impressive story on climate impacts, “Climate Catastrophe? Here’s What the U.S. Could Look Like in 2100.” Those impacts should be motivation enough for action as is, but in fact the story would be a much more accurate portrayal of the latest science with just the tiniest of changes: replace “in 2100″ with “post-2050.” MSN asserts with unusual bluntness:
… you wonder, “Is climate disaster already upon us?”
Scientists say the answer is “yes.” We are now experiencing the effects of human-caused climate change and, even if we drastically alter our polluting behavior today, we’ll continue to see changes over the next two to three decades. This change is irreversible, and researchers predict it may be worse than the depressing situation Al Gore foretold in An Inconvenient Truth.
Precisely. Here is the region-by-region warning “if we don’t act now”:
Pacific Northwest: Washington, Oregon, Idaho and Alaska
What we could see in 2100 post-2050: Heavier rains, dramatic warming over higher latitudes and sea-level rise.
… “There will be very dramatic warming over the higher latitudes of both hemispheres,” says [Jim Hurrell, PhD, a senior atmospheric scientist with the National Center for Atmospheric Research (NCAR)]. Studies on temperature changes that have already occurred show that Alaska has experienced a 3.6 degree Fahrenheit increase since 1951….
And the planet as a whole has only warmed a little over 1°F since then — so imagine how hot the West and Alaska will get when the planet as a whole warms several times that post-2050.
The Northwest will also be affected by the anticipated two to three feet of sea level rise…
What we could see in 2100 post-2050: Shorter snow season, early snowmelt, drought, wildfire and water issues
… “In the future, the snow season will get shorter, the snow pack will be less, and runoff could easily occur a month or two earlier,” says Trenberth [head of the Climate Analysis Section at NCAR)]. “Instead of having peak runoff in June, it could happen in April. Then, by the time you get to June, [the entire region] is a lot drier” [than it is now].
What we could see in 2100 post-2050: Harsher storms, extreme sea level rise and flooding
… Hurrell: “On average, global sea levels will go up two to three feet.” But scientists expect that in some coastal cities, such as Boston and New York, complex ocean currents that will change as our climate changes will add an extra 8 inches to that increase in water level.
[Note: If anybody has a source for that extra 8 inches, let me know.]
What we could see in 2100 post-2050: Hurricanes, wind damage, storm surges, flooding, extra sea level rise
… The Southeast can also expect more extreme hurricanes, similar to the conditions that came together around Hurricane Katrina. “There are three main risks,” says Trenberth. “There is risk for increased wind damage, risk for a storm surge, which is very coastal and exacerbated by higher sea levels, and then a bit further inland, there is an increased risk of flooding from torrential rains.”
See “Nature: Hurricanes ARE getting fiercer “” and it’s going to get much worse” and links therein for further discussion.
What we could see in 2100 post-2050: Stronger storms (tornados, heavy rains) occurring throughout the year and warmer winters
… Some estimates predict temperature changes as high as 5 to 12 degrees Fahrenheit in winter, and 5 to 20 degrees Fahrenheit in summer by 2100.
Warmer winters can lead to an increase in infectious diseases such as Lyme disease, West Nile virus and dengue fever, says Knowlton, as warmer winter weather allows insect populations to remain active longer each year.
What we could see in 2100 post-2050: Drought and water shortages, heat waves and wildfire
… “The increased heating of the earth’s surface not only raises temperatures, but it increases evaporation which makes dry soils even drier,” says Hurrell. “Droughts will become more severe, frequent and longer lasting.”
This is clearly a post-2050 impact. Two years ago, Science (subs. req’d) published research that “predicted a permanent drought by 2050 throughout the Southwest” on our current emissions path “” levels of aridity comparable to the 1930s Dust Bowl would stretch from Kansas to California. The Bush Administration itself reaffirmed this conclusion in December (see US Geological Survey stunner: SW faces “permanent drying” by 2050).
Let me end with the key points:
“What happens in the next 20 or 30 years is largely already determined.” says Kevin Tranberth, ScD, head of the Climate Analysis Section at the National Center for Atmospheric Research (NCAR). “Carbon dioxide concentrations in the atmosphere have already increased by more than 35 percent since pre-industrial times, owing to human activities. Over half of that increase has occurred since 1970.”
Although this prognosis seems dire, there is hope. While we can’t change the polluting that has already occurred, we can make changes now that will leave a cleaner world for our children and grandchildren…. Tranberth agrees. “If we act now, the benefit comes about 30 to 40 years from now,” he says. “We can still have a big impact on what happens in the second half of this century.”
The time to act is now.