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Long-term Cycles

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Expert Hurricane Forecaster Says Upcoming 2017 Season Likely To Be “Worst/Costliest” In 12 Years! Ocala, FL (PRWEB) Global Weather Oscillations (GWO) veteran meteorologist David Dilley says in his early forecast that the 2017 Atlantic hurricane season will be stronger than last year – with the potential for 6 named storms making United States landfalls.

Expert Hurricane Forecaster Says Upcoming 2017 Season Likely To Be “Worst/Costliest” In 12 Years!

It will also be the most dangerous since the 2005 season, which saw 5 hurricane landfalls and 2 tropical storms. GWO has issued the most accurate preseason predictions of any organization the past 8 years, including last years’ prediction that the “Atlantic Basin” (which includes the Caribbean Sea and Gulf of Mexico) – would enter a Climate Pulse Hurricane Enhancement Cycle in 2016. AMO: Atlantic Climate Pulse. I was inspired by David Dilley’s weather forecasting based upon Atlantic water pulsing into the Arctic Ocean (see post: Global Weather Oscillations).

AMO: Atlantic Climate Pulse

So I went looking for that signal in the AMO dataset, our best long-term measure of sea surface temperature variations in the North Atlantic. For this purpose, I downloaded the AMO Index from Kaplan SST v.2, the unaltered and untrended dataset. By definition, the data are monthly average SSTs interpolated to a 5×5 grid over the North Atlantic basically 0 to 70N.

For an overview the graph below presents a comparison between Annual, March and September averages from 1856 to 2016 inclusive. The Bray (Hallstatt) Cycle. By Andy May and Javier The evidence for a persistent irregular climate cycle with a period of 2400 ±200 years is strong.

The Bray (Hallstatt) Cycle

There is compelling evidence of a solar cycle of about the same length and phase; suggesting that the solar cycle might be causing the climate cycle. We will present a summary of the evidence, beginning with the original paleontological evidence, followed by the cosmogenic radionuclide (10Be or Beryllium-10 and 14C or Carbon-14) evidence. For more information, a bibliography of many papers discussing topics relevant to the Bray (Hallstatt) cycle can be found here. Only a small portion of the relevant papers are mentioned in this summary post. Solar variability and the Earth’s climate. By Andy May According to Javier and the IPCC total solar radiation output varies little, less than 0.1%.

Solar variability and the Earth’s climate

This is only 0.7 to 1.4 Watts/m2 and converted to incident radiation striking the Earth this reduces to about 0.05 to 0.4 W/m^2. 1,500-year cycle in the Arctic Oscillation identified in Holocene Arctic sea-ice drift : Nature Geoscience : Nature Research. Affiliations Department of Ocean, Earth, & Atmospheric Sciences, Old Dominion University, Norfolk, Virginia 23529, USA Dennis A.

1,500-year cycle in the Arctic Oscillation identified in Holocene Arctic sea-ice drift : Nature Geoscience : Nature Research

Darby & Chester E. Grosch Department of Geology, Kent State University, Kent, Ohio 44242, USA Joseph D. Nature Unbound I: The Glacial Cycle. By Javier Insights into the debate on whether the Holocene will be long or short.

Nature Unbound I: The Glacial Cycle

Summary: Milankovitch Theory on the effects of Earth’s orbital variations on insolation remains the most popular explanation for the glacial cycle since the early 1970’s. According to its defenders, the main determinant of a glacial period termination is high 65° N summer insolation, and a 100 kyr cycle in eccentricity induces a non-linear response that determines the pacing of interglacials. Based on this theory some authors propose that the current interglacial is going to be a very long one due to a favorable evolution of 65° N summer insolation. Nature Unbound II: The Dansgaard- Oeschger Cycle. By Javier Dansgaard-Oeschger (D-O) events are the most dramatic and frequent abrupt climate change events in the geological record.

Nature Unbound II: The Dansgaard- Oeschger Cycle

They are usually explained as the result of an Atlantic Ocean salinity oscillation paced by internal variability. Available evidence however supports that they are the result of an externally paced oceanic-sea ice interaction in the Norwegian Sea. Arctic Iris Effect Dansgaard Oeschger Events and Failed Climate Models. How Much Does the Arctic Iris Effect Explain Recent Warming, 1930s Warming and Dansgaard-Oeschger Events?

Arctic Iris Effect Dansgaard Oeschger Events and Failed Climate Models

During the last Ice Age, Greenland’s average temperatures dramatically rose on average every 1500 years by 10°C +/- 5°C in a just matter of one or two decades, and then more gradually cooled as illustrated in Figure 1 below (8 of the 25 D-O events are numbered in red on upper graph; from Ahn 2008). These extreme temperature fluctuations between cold “stadials” that lasted about a thousand years and warm “interstadials” lasting decades are dubbed Dansgaard-Oeschger events (D-O events). These rapid temperature fluctuations not only rivaled the 100,000? Just 25 years ago most climate researchers were hesitant to accept initial Greenland ice core evidence that suggested such abrupt D-O warming events (Dansgaard 1985). Changes in CO2 concentration are unlikely to have had much impact on D-O events (3rd graph from the top in Figure 1). The timing of interglacials.

By Andy May P.

The timing of interglacials

C. Tzedakis and co-authors have just published a new paper in the February 23, 2017 issue of Nature entitled “A simple rule to determine which insolation cycles lead to interglacials.” The paper introduces new rules for defining interglacial periods in the geological record. The Arctic Iris Effect, Dansgaard-Oeschger Events, and Climate Model Shortcomings. Lesson from Climate Past – part 1.

Guest essay by Jim Steele Director emeritus Sierra Nevada Field Campus, San Francisco State University and author of Landscapes & Cycles: An Environmentalist’s Journey to Climate Skepticism Dansgaard Oeschger Events and the Arctic Iris Effect During the last Ice Age, Greenland’s average temperatures dramatically rose on average every 1500 years by 10°C +/- 5°C in a just matter of one or two decades, and then more gradually cooled as illustrated in Figure 1 below (8 of the 25 D-O events are numbered in red on upper graph; from Ahn 2008).

The Arctic Iris Effect, Dansgaard-Oeschger Events, and Climate Model Shortcomings. Lesson from Climate Past – part 1.

An alternate theory for the terrestrial ice-age trigger. [Note: This essay discusses a theory that some people might consider as impossible, and it may very well be, even though there is some support for the idea that continental position plays a role in major ice ages. As seen below, Milankovitch cycles resulting in insolation variance is a leading theory that seems much more plausible as a driver than the one proposed by Voisin below. However, exposing such ideas to open discussion is the surest way to sort out the possible from the impossible, and Mr. Voisin expects such challenges. So, beat it up, and let’s see what is left. – Anthony] The Intriguing Problem Of The Younger Dryas—What Does It Mean And What Caused It?

This is a follow up posting to Younger Dryas -The Rest of the Story! Guest post by Don J. Easterbrook Dept. of Geology, Western Washington University. The Younger Dryas was a period of rapid cooling in the late Pleistocene 12,800 to 11,500 calendar years ago. It followed closely on the heels of a dramatically abrupt warming that brought the last Ice Age to a close (17,500 calendar years ago), lasted for about 1,300 years, then ended as abruptly as it started. The cause of these remarkably sudden climate changes has puzzled geologists and climatologists for decades and despite much effort to find the answer, can still only be considered enigmatic.