RealClimate logo


Unforced variations: Oct 2017

Filed under: — group @ 1 October 2017

This month’s open thread. Carbon budgets, Arctic sea ice minimum, methane emissions, hurricanes, volcanic impacts on climate… Please try and stick to these or similar topics.

358 Responses to “Unforced variations: Oct 2017”

  1. 351
  2. 352
    Killian says:

    #344 nigelj said -1+1

    52 years of life and I have never seen one person work so hard to defend their ego with so little justification. Seriously, like arguing with an ignorant HS freshman. Still, the Useful Idiot is useful because they provide the opportunity to achieve ends. In this case, a better understanding of sustainability for some reading those excruciatingly inane, nonsensical posts.

  3. 353
    David B. Benson says:

    MA Roger @346 — I added more at my link, including the Peter Molnar work which argues the irrelevancy of the closure of the Panama seaway; it happened much earlier, as he shows.

    Carbon dioxide levels have been generally falling for the entire Cenozoic. RA Brenner, 2008, argues, using his Geocarb model, that this is the result of vascular plants.

    So the more interesting question is why the first glaciation at close to 3 million years ago.

  4. 354
    David B. Benson says:

    Here is a discussion piece about a paper by Deconto & Pollard, Nature 2017, who offer a new mechanism for glacial collapse:
    http://www.nature.com/news/antarctic-model-raises-prospect-of-unstoppable-ice-collapse-1.19638
    Seems that it should be controversial, although it sounds plausible.

  5. 355
    nigelj says:

    Killian @352

    Killian can’t handle criticism (highly accurate criticism) so attacks the person, time and time again. Its all he has.

  6. 356
    Killian says:

    In a nutshell… Isht! Pay very, very close attention to this article. It is an omen.

    http://www.bbc.co.uk/news/resources/idt-sh/death_of_the_nile

  7. 357
    Killian says:

    Re #354, I think the quote below is wishful thinking.

    The good news, he says, is that it projects little or no sea-level rise from Antarctic melt if greenhouse-gas emissions are reduced quickly enough to limit the average global temperature rise to about 2 °C.

    There are indications of exponential increases in SLR, with Hansen, et al., seeing potential for 10 or even 5 year doubling times. That’s meters this century. I’ve done the math, but don’t trust my math, but 5 year doublings equals a *lot* of SLR.

    Risk assessment says…

  8. 358
    Thomas says:

    from a link by another poster here:

    Record surge in atmospheric CO2
    This year’s greenhouse gas bulletin produced by the WMO is based on measurements taken in 51 countries. Research stations dotted around the globe measure concentrations of warming gases including carbon dioxide, methane and nitrous oxide.

    The figures published by the WMO are what’s left in the atmosphere after significant amounts are absorbed by the Earth’s “sinks”, which include the oceans and the biosphere

    2016 saw average concentrations of CO2 hit 403.3 parts per million, up from 400ppm in 2015.

    “It is the largest increase we have ever seen in the 30 years we have had this network,” Dr Oksana Tarasova, chief of WMO’s global atmosphere watch programme, told BBC News.

    “The largest increase was in the previous El Niño, in 1997-1998, and it was 2.7ppm; and now it is 3.3ppm. It is also 50% higher than the average of the last 10 years.”

    The study notes that since 1990 there has been a 40% increase in total radiative forcing. That’s the warming effect on our climate of all greenhouse gases.

    “Geological-wise, it is like an injection of a huge amount of heat,” said Dr Tarasova.

    “The changes will not take 10,000 years, like they used to take before; they will happen fast. We don’t have the knowledge of the system in this state; that is a bit worrisome!”

    According to experts, the last time the Earth experienced a comparable concentration of CO2 was three to five million years ago, in the mid-Pliocene Epoch. The climate then was 2-3C warmer, and sea levels were 10-20m higher due to the melting of Greenland and the West Antarctic ice sheets.

    Other experts in the field of atmospheric research agreed that the WMO findings were a cause for concern.

    “The 3ppm CO2 growth rate in 2015 and 2016 is extreme – double the growth rate in the 1990-2000 decade,” Prof Euan Nisbet from Royal Holloway University of London, UK, told BBC News.
    30 October 2017
    http://www.bbc.com/news/science-environment-41778089