Tanada wrote:..... as I have myself pointed out elsewhere and has been shown a gazillion times around here
a) the weather in the midwest, floods and all, is not "unprecedented", we had worse spring weather when Clinton was in his first full year in office, just for one example.
b) This is a long term climate event mostly driven by the el Nino cycle with particularly intense events taking place every few decades. 1992-93, 1997-98, 2011-2012 and this year are all extremely warm wet summers driven by the cycle.
Tanada wrote:.The whole 'record number of tornadoes' thing is VERY deceptive because over the years almost all tornadoes had to be spotted and reported by a trusted observer to be recorded as a tornado. More recently a lot of weather People are using Doppler radar returns to identify every circular motion in a thunderstorm as a bonified tornado even though they do not meet the traditional meaning of the terminology.
Plantagenet wrote:Maybe Guy is onto something there.....time will tell.
CHEERS!
derhundistlos wrote:AdamB-
Please provide a source for your three claims that McPherson predicted the end of civilization for dates already passed.
Thanks.
Revi wrote:Here's a talk by Guy McPherson.
A lot of what he says seems very possible.
Greenland, Antarctica, South America, the Himalayas—it’s all going, the ice is leaving the Earth. This is a whirl-wind roundup of new science with Ottawa climate expert Paul Beckwith. We talk pollution (is it saving us?), vanishing glaciers, Tasmanian dry lightening fires, James Hansen’s latest, tech to draw down carbon dioxide, and why this scientist made 500 videos to educate and warn the public via YouTube. Catch up quick, with this week’s Radio Ecoshock.
WE ARE WITNESSING THE END OF THE AGE OF ICE ON EARTH
Sea level rise is going to be wicked this century, and for centuries after that. We will redraw the maps, withdraw from our ports, lose the weather we need for agriculture, and maybe regroup into tribes that will survive. New revelations from climate science are coming in so fast, no single scientist or radio host can keep track of it all. It is like standing in front of a fire-hose.
THE POLAR VORTEX AND THE WINTER OF CLIMATE CHANGE
When we think of global warming, we imagine hot days, way too hot days and fires. But Paul and I discuss what I call “The Winter of Climate Change”. A while back we had pro meteorologist Judah Cohen on the air. He said the term “polar vortex” really only applies to events in the Stratosphere, but now it has been stolen and popularized by TV weather forecasters. What we are really describing is a blast of super-cold Arctic air escaping lower down to the mid-latitudes, partly due to a weak and wavering Jet Stream.
In Paul’s YouTube videos, he often talks about whip-saw events where temperatures can shift as much as 70F (21C) within 24 hours. This is very hard on human infrastructure, but it’s really toxic to plants. I worry we’ll see tree die-off, and lost perennials from those sub-zero chills followed by spring-like warmth the next day.
A week ago photos in the Tasmanian highlands of Australia showed giant forest fires on the horizon, during record hot heat. Fast forward to Tuesday 12th, and you would see an unusual summer snow storm at the same spot! Whipsaw.
ICE SHEET LOSS
There is new science out, saying “Melting ice sheets may cause ‘climate chaos’ according to new modeling” and “Current international climate policies do not take into account full effects on global climate”.
Professor Natalya Gomez, from the Department of Earth and Planetary Sciences at McGill modeled projected changes to water levels around the globe as ice melts into the ocean. The ice sheet simulations suggest that the fastest increase in the rise of sea levels is likely to occur between 2065 and 2075. Melting ice sheets will affect water temperatures and circulation patterns in the world’s oceans, which will in turn affect air temperatures in a complex ice-ocean-atmosphere feedback loop.
“Water levels would not simply rise like a bathtub,” says Gomez. “Some areas in the world, such as the island nations in the Pacific, would experience a large rise in sea level, while close to the ice sheets the sea level would actually fall.”
The effects of ice sheet melt are far more widespread than simply leading to changes in sea levels. As warmer melt water enters the oceans, major currents such as the Gulf Stream will be significantly weakened. This will lead to warmer air temperatures in the high Arctic, Eastern Canada and Central America, and cooler temperatures over northwestern Europe.”
HEAT RECORDS AND PREDICTIONS
People mistakenly think Tasmania is tropical, but it is the closest part of Australia to Antarctica. The weather should be very temperate if not cold and wet there, most of the year. Tasmania has world-class forests that have not burned in thousands of years, until the last few years. Like me in British Columbia, Tasmanians have felt the terror of wildfires that plague the rest of Australia, now that every year is a fire year. Nowhere is safe anymore.
THE HOT SEAS
“Our model-based analysis suggests that nearly half of the industrial-era increases in global OHC have occurred in recent decades, with over a third of the accumulated heat occurring below 700m and steadily rising.”
AdamB wrote:Come on Revi, you aren't a 10 year old who with wide eyes believes any crap spoon fed them by the adults.
Do you have ANY information that his data leading to his proclamations of end of civilization are any more right today, then they were the other times when he was wrong?
Aerosol masking effect, global industry down a third, temperature rise of one degree Celcius in a week or so.The funny thing is that the thing that could save some of us is Peak Oil. If we can't get our hands on the stuff and burn it maybe we have a chance.
As above image shows, aerosols result from burning fuel in industrial processes and transport, and for purposes of heating or lighting buildings (such as with woodburners, furnaces, stoves, candles, oil lamps and open fireplaces) or for preparing food and boiling water. Aerosols can also be caused by open fires that can be lit to make charcoal, burn waste, turn forests into pasture, etc. Global warming increases the fire danger (i.e. in frequency, intensity, duration and size) and thus emissions from both forest fires and controlled open fires (backburning and reducing waste).
A 2008 study by Ramanathan et al. mentions figures from other studies for the radiative forcing (RF) of black carbon, i.e. figures ranging from 0.4 Watts per square meter (W/m²) to 1.2 W/m². A 2013 study by Bond et al. calculates that black carbon has a warming effect of about 1.1 W/m². Above image highlights this figure of 1.1 W/m² of radiative forcing (RF), while warning that RF could be as high as 2.1 W/m². In addition to black carbon, sulfur dioxide (SO₂) has an important impact, as discussed in the box below.
http://theconversation.com/masking-and-unmasking-of-global-warming-by-aerosols-19990A 2013 study by Levy et al. concludes that emission reductions by 35%–80% in anthropogenic aerosols and their precursors would result in some 1°C of additional warming. A 2016 paper by Zhang et al. calculates that from 1850 to 2010, anthropogenic aerosols brought about a decrease of about 2.53°C. Also see the study by Rosenberg et al. and the news release.
Anthropogenic aerosols are also suppressing the Pacific Decadal Oscillation, making that less heat gets transferred from oceans to the atmosphere. Recent research concludes that future reduction of anthropogenic aerosol emissions, particularly from China, would promote positive Pacific Decadal Oscillation, thus further speeding up warming over the coming years.
Dimethyl sulphide emissions from oceans constitute the largest natural source of atmospheric sulphur, and such emissions can decrease with ongoing ocean acidification and climate change. This could particularly impact specific regions such as Antarctica, speeding up warming and loss of sea ice there, as discussed at this paper.
Aside from carbon dioxide, another human influence on climate comes from aerosols, which exert a cooling effect. Aerosols (that is, atmospheric particles, not propellants used in spray cans) have masked some of the warming that is caused by increasing greenhouse gases.
Without the masking effect of aerosols, global temperatures would have increased more than they have since the 19th century.
I recently led a study that examined the effects of declining aerosols in 21st century climate projections. We found that global warming is likely to accelerate in the next few decades, if the cooling influence of human-generated aerosols declines as predicted.
Abstract
[1] Using the Geophysical Fluid Dynamics Laboratory's (GFDL's) fully coupled chemistry‐climate (ocean/atmosphere/land/sea ice) model (CM3) with an explicit physical representation of aerosol indirect effects (cloud‐water droplet activation), we find that the dramatic emission reductions (35%–80%) in anthropogenic aerosols and their precursors projected by Representative Concentration Pathway (RCP) 4.5 result in ~1 °C of additional warming and ~0.1 mm day−1 of additional precipitation, both globally averaged, by the end of the 21st century. The impact of these reductions in aerosol emissions on simulated global mean surface temperature and precipitation becomes apparent by mid‐21st century. Furthermore, we find that the aerosol emission reductions cause precipitation to increase in East and South Asia by ~1.0 mm day−1 through the second half of the 21st century. Both the temperature and the precipitation responses simulated by CM3 are significantly stronger than the responses previously simulated by our earlier climate model (CM2.1) that only considered direct radiative forcing by aerosols. We conclude that the indirect effects of sulfate aerosol greatly enhance the impacts of aerosols on surface temperature in CM3; both direct and indirect effects from sulfate aerosols dominate the strong precipitation response, possibly with a small contribution from carbonaceous aerosols. Just as we found with the previous GFDL model, CM3 produces surface warming patterns that are uncorrelated with the spatial distribution of 21st century changes in aerosol loading. However, the largest precipitation increases in CM3 are colocated with the region of greatest aerosol decrease, in and downwind of Asia.
The world’s scientific community has known for a long time that global warming is caused by manmade emissions in the form of greenhouse gases, while global cooling is caused by air pollution in the form of aerosols.
In a new study published in the journal Science, Hebrew University of Jerusalem Prof. Daniel Rosenfeld argues that the degree to which aerosol particles cool the earth has been grossly underestimated.
ABSTRACT
The effective radiative forcing (ERF), as newly defined in the Intergovernmental Panel on Climate Change's Fifth Assessment Report (IPCC AR5), of three anthropogenic aerosols [sulphate (SF), black carbon (BC), and organic carbon (OC)] and their comprehensive climatic effects were simulated and discussed, using the updated aerosol‐climate online model of BCC_AGCM2.0.1_CUACE/Aero. From 1850 to 2010, the total ERF of these anthropogenic aerosols was −2.49 W m−2, of which the aerosol–radiation interactive ERF (ERFari) and aerosol–cloud interactive ERF (ERFaci) were ∼ −0.30 and −2.19 W m−2, respectively. SF was the largest contributor to the total ERF, with an ERF of −2.37 W m−2. The ERF of BC and OC were 0.12 and −0.31 W m−2, respectively. From 1850 to 2010, anthropogenic aerosols brought about a decrease of ∼2.53 K and ∼0.20 mm day−1 in global annual mean surface temperature and precipitation, respectively. Surface cooling was most obvious over mid‐ and high latitudes in the northern hemisphere (NH). Precipitation change was most pronounced near the equator, with decreased and increased rainfall to the north and south of the equator, respectively; this might be largely related to the enhanced Hadley Cell in the NH. Relative humidity near surface was increased, especially over land, due to surface cooling induced by anthropogenic aerosols. Cloud cover and water path were increased, especially in or near the source regions of anthropogenic aerosols. Experiments based on the Representative Concentration Pathway (RCP) 4.5 given in IPCC AR5 shows the dramatic decrease in three anthropogenic aerosols in 2100 will lead to an increase of ∼2.06 K and 0.16 mm day−1 in global annual mean surface temperature and precipitation, respectively, compared with those in 2010.
evilgenius wrote:The way to respond is to become increasingly complex.
The way to respond is to become increasingly complex.
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