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Climate Change in theClimate Change in thePacific NorthwestPacific Northwest
and Elsewhereand Elsewhere
George H. TaylorGeorge H. TaylorJanuary, 2012January, 2012
The question everyone is asking:The question everyone is asking:
What causes climate to change?
What causes climate to change?
Is it human causes?Is it human causes?Greenhouse gases
Land use changeSmoke, dust, aerosols
…and stuff.
Greenhouse gasesLand use change
Smoke, dust, aerosols…and stuff.
Is it natural causes?Is it natural causes?Sunlight variations
Ocean conditionsVolcanoes
…and stuff.
Sunlight variationsOcean conditions
Volcanoes…and stuff.
All else being equal, increasing the greenhouse gases should
increase temperature.
All else being equal, increasing the greenhouse gases should
increase temperature.
The only questions are,
1. By how much?
2. How do we measure this?
The only questions are,
1. By how much?
2. How do we measure this?
“Alarmists”“Alarmists”
Climate change is occurring far faster than even the worst predictions of the UN's Nobel Prize-winning scientific panel on climate change foresaw, Al Gore warned.
New evidence shows "the climate crisis is significantly worse and unfolding more rapidly than those on the pessimistic side of the IPCC projections had warned us."
Climate change is occurring far faster than even the worst predictions of the UN's Nobel Prize-winning scientific panel on climate change foresaw, Al Gore warned.
New evidence shows "the climate crisis is significantly worse and unfolding more rapidly than those on the pessimistic side of the IPCC projections had warned us."
“Alarmists”“Alarmists”
“I believe it is appropriate to have an over-representation of factual presentations on how dangerous it [anthropogenic global warming] is, as a predicate for opening up the audience to listen to what the solutions are.” Al Gore
“I believe it is appropriate to have an over-representation of factual presentations on how dangerous it [anthropogenic global warming] is, as a predicate for opening up the audience to listen to what the solutions are.” Al Gore
“Deniers”“Deniers”
"I think those people are in such a tiny, tiny minority now with their point of view," Gore continues. "They're almost like the ones who still believe that the Moon landing was staged in a movie lot in Arizona and those who believe the world is flat."
Al Gore, 2008
"I think those people are in such a tiny, tiny minority now with their point of view," Gore continues. "They're almost like the ones who still believe that the Moon landing was staged in a movie lot in Arizona and those who believe the world is flat."
Al Gore, 2008
Alarmists say:Alarmists say:
Scientists are very certain that the Pacific Northwest is warming and that since 1975 the warming is best explained by human-caused changes in greenhouse gases.
Scientists are very certain that the Pacific Northwest is warming and that since 1975 the warming is best explained by human-caused changes in greenhouse gases.
Oregon Strategy for Greenhouse Gas ReductionsReport to the GovernorThe Governor’s Advisory Group on Global Warming
Deniers say:Deniers say:
In Oregon, in the Northwest, in the US, the warmest decade of the last 100 years occurred in the 1930s. The temperature change has had a pronounced cyclical nature rather than a simple increase. Temperature extremes (high and low) are becoming less common in recent decades.
In Oregon, in the Northwest, in the US, the warmest decade of the last 100 years occurred in the 1930s. The temperature change has had a pronounced cyclical nature rather than a simple increase. Temperature extremes (high and low) are becoming less common in recent decades.
Alarmists say:Alarmists say:
“Last month, a study released by the University of Washington shows we’ve already lost 20% of our snow pack over the last 30 years.”
Gov. Christine Gregoire, 2009
“Last month, a study released by the University of Washington shows we’ve already lost 20% of our snow pack over the last 30 years.”
Gov. Christine Gregoire, 2009
Deniers say:Deniers say:
In Oregon, in the Northwest, snow pack shows a cyclical behavior rather than a simple decrease.
There is no significant long-term decrease if period-of-record data are used. The same is true for North American and Northern Hemisphere
snow extent.
In Oregon, in the Northwest, snow pack shows a cyclical behavior rather than a simple decrease.
There is no significant long-term decrease if period-of-record data are used. The same is true for North American and Northern Hemisphere
snow extent.
Alarmists say:Alarmists say:
CO2 levels are a dominant factor in climate change.
CO2 levels are a dominant factor in climate change.
Deniers say:Deniers say:
Climate changes primarily because of the influence of the oceans (esp. the Tropical
Pacific) and changes in sunlight.
Climate changes primarily because of the influence of the oceans (esp. the Tropical
Pacific) and changes in sunlight.
Alarmists say:Alarmists say:
Hurricanes are increasing in intensity.Hurricanes are increasing in intensity.
Alarmists say:Alarmists say:
The Arctic and Antarctic are melting.The Arctic and Antarctic are melting.
Temperatures did increase from 1970 to 2000 (Polyakov, et al, 2003)Temperatures did increase from 1970 to 2000 (Polyakov, et al, 2003)
Arctic surface air temperature anomalies
Antarctic Sea Ice Area Anomalies, 1978-2005, from NSIDC (2006)
Antarctic temperatures show a slight cooling over 30 years
Deniers say:Deniers say:
At Glacier Park, over 80% of the melt occurred between 1920 and 1940, before the CO2 enhancement of WWII. The main mode of variability appears to be the PDO.
Worldwide, many glaciers have shrunk, but others are growing (e.g., Shasta, Argentina, Alaska)
At Glacier Park, over 80% of the melt occurred between 1920 and 1940, before the CO2 enhancement of WWII. The main mode of variability appears to be the PDO.
Worldwide, many glaciers have shrunk, but others are growing (e.g., Shasta, Argentina, Alaska)
My Opinion on AGW:
1. Human activities DO affect climate, in a variety of ways. Greenhouse gases are just one parameter.
2. Natural variations affect climate. I believe that they have been more significant influences on climate because they do a much better job of explaining observed variations.
3. Effects of future changes in CO2 are likely to be modest and manageable.
4. Many aspects of climate remain poorly understood.
Deniers say:Deniers say:
Actually, CO2 changes have always followed temperature changes.
Actually, CO2 changes have always followed temperature changes.
Indermühle et al. (GRL, vol. 27, p. 735, 2000), who find that CO2 lags behind the temperature by 1200±700 years.
Fischer et al. (Science, vol 283, p. 1712, 1999) reported a time lag 600±400 yr during early de-glacial changes in the last 3 glacial–
interglacial transitions.
Siegenthaler et al. (Science, vol. 310, p. 1313, 2005) find a best lag of 1900 years in the Antarctic data.
Monnin et al. (Science vol 291, 112, 2001) find that the start of the CO2 increase in the beginning of the last interglacial lagged the
start of the temperature increase by 800 years.