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What's Causing The Hurricanes? (yahoo.com)

An anonymous reader quotes AFP: Hurricane Irma, now taking aim at Florida, has stunned experts with its sheer size and strength, churning across the ocean with sustained Category 5 winds of 183 miles per hour (295 kilometers per hour) for more than 33 hours, making it the longest-lasting, top-intensity cyclone ever recorded. Meanwhile Jose, a Category 4 on the Saffir Simpson scale of 1 to 5, is fast on the heels of Irma, pummeling the Caribbean for the second time in the span of a few days. Many have wondered what is contributing to the power and frequency of these extreme storms. "Atlantic hurricane seasons over the years have been shaped by many complex factors," said Jim Kossin, a NOAA hurricane scientist at the University of Wisconsin. "Those include large scale ocean currents, air pollution -- which tends to cool the ocean down -- and climate change"...

Some think a surge in industrial pollution after World War II may have produced more pollutant particles that blocked the Sun's energy and exerted a cooling effect on the oceans. "The pollution reduced a lot of hurricane activity," said Gabriel Vecchi, professor of geosciences at Princeton University's Environmental Institute. Pollution began to wane in the 1980s due to regulations such as the Clean Air Act, allowing more of the Sun's rays to penetrate the ocean and provide warming fuel for storms. Vecchi said the "big debate" among scientists is over which plays a larger role -- variations in ocean currents or pollution cuts. There is evidence for both, but there isn't enough data to answer a key question...

The burning of fossil fuels, which spew greenhouse gases into the atmosphere and warm the Earth, can also be linked to a rise in extreme storms in recent years. Warmer ocean temperatures yield more moisture, more rainfall, and greater intensity storms. "It is not a coincidence that we're seeing more devastating hurricanes," climatologist Michael Mann of Penn State University told AFP in an email. "Over the past few years, as global sea surface temperatures have been the warmest on record, we've seen the strongest hurricanes -- as measured by peak sustained winds -- globally, in both Southern and Northern Hemisphere, in both Pacific and now, with Irma, the open Atlantic," he added. "The impacts of climate change are no longer subtle. We're seeing them play out in real time, and the past two weeks have been a sadly vivid example."

2 of 442 comments (clear)

  1. All about that bass by PopeRatzo · · Score: 1, Interesting

    The hurricanes are caused by too much butt sex:

    http://metro.co.uk/2017/09/06/...

    http://www.rightwingwatch.org/...

    --
    You are welcome on my lawn.
  2. Re:One active season and now everything is differe by Anonymous Coward · · Score: 2, Interesting

    "[W]e use a diatom record from El Junco Lake, Galápagos, to produce a calibrated, continuous record of sea surface temperature in the eastern tropical Pacific Ocean at subdecadal resolution, spanning the past 1,200 years. Our reconstruction reveals that the most recent 50 years are the warmest 50-year period within the record."
    J. L. Conroy, et al., "Unprecedented recent warming of surface temperatures in the eastern tropical Pacific Ocean", Nature Geoscience, vol. 2, pp. 46-50, 2009.

    "We provide updated estimates of the change of ocean heat content and the thermosteric component of sea level change of the 0–700 and 0–2000 m layers of the World Ocean for 1955–2010. The heat content of the World Ocean for the 0–2000 m layer increased by 24.0 ± 1.9 × 1022 J (±2S.E.) corresponding to a rate of 0.39 W m2 (per unit area of the World Ocean) and a volume mean warming of 0.09C."
    S. Levitus, et al, "World ocean heat content and thermosteric sea level change (0–2000 m), 1955–2010," Geophysical Research Letters, vol. 39(10), L10603, 2009.

    "We use four of the world's longest calibrated daily time series to show that trends in surface temperatures in the North and Baltic Seas now exceed those at any time since instrumented measurements began in 1861 and 1880. Temperatures in summer since 1985 have increased at nearly triple the global warming rate, which is expected to occur during the 21st century and summer temperatures have risen two to five times faster than those in other seasons."
    B. R. Mackenzie and D. Schiedek, "Daily ocean monitoring since the 1860s shows record warming of northern European seas", Global Change Biology, vol. 13(7), pp. 1335–1347, 2007.

    "Here, we use the TEX86 temperature proxy, the weight per cent of biogenic silica and charcoal abundance from Lake Tanganyika sediment cores to reconstruct lake-surface temperature, productivity and regional wildfire frequency, respectively, for the past 1,500 years. We detect a negative correlation between lake-surface temperature and primary productivity, and our estimates of fire frequency, and hence humidity, preclude decreased nutrient input through runoff as a cause for observed periods of low productivity. We suggest that, throughout the past 1,500 years, rising lake-surface temperatures increased the stratification of the lake water column, preventing nutrient recharge from below and limiting primary productivity. Our records indicate that changes in the temperature of Lake Tanganyika in the past few decades exceed previous natural variability."
    J. E. Tierney, et al., "Late-twentieth-century warming in Lake Tanganyika unprecedented since AD 500", Nature Geoscience, vol. 3, pp. 422-425, 2010.

    These are only a subset of the hundreds of articles through which I've read over the years. All of these studies analyze different data modalities and come to the same conclusions; you could do a meta-analysis to quantitatively show that this is true. Moreover, the period of time in which these studies consider ranges from decades to centuries and even to multiple millennia.

    It's therefore not a stretch to conclude that your claims are wrong: there has been unprecedented warming in the past hundred years when compared to the past several millennia.