On the coming El Nino

Given that I’ve written about this before I thought I may as well post this short video of Kevin Trenberth talking about the possibility of an El Niño later this year. According to Kevin Trenberth, it’s not so much if we’ll get an El Niño later this year, but how big it’s going to be.

There’s something I’ve been thinking about that I thought I might mention briefly. There seem to be some who think that because we can associate a particular warming event with – for example – an El Niño event, that somehow this warming is natural and not anthropogenic. It’s as if some think that there must be some kind of anthropogenic surface warming mechanism.

Well, there isn’t really. What we’re doing is increasing the greenhouse gas concentrations in the atmosphere, and this is acting to trap more and more energy in the climate system. We can certainly think of the long-term surface warming trend as being representative of an anthropogenic warming rate, since this might represent how the surface would warm if the system were completely steady and every part of the system warmed at a steady rate. However, the system isn’t completely steady and is clearly highly variable. All of the variability, however, is natural. Anthropogenic influences may well influence this variability, but there isn’t some variability that is anthropogenic and some that’s isn’t.

What I’m really getting at is that the change in radiative forcing is almost entirely anthropogenic and hence that we’re warming is also almost entirely anthropogenic. Just because we can associate some warming with a natural mechanism, doesn’t mean that that warming isn’t anthropogenic. The variability may well mean that sometimes the surface warms faster than the long-term trend, and sometimes slower, but while we still have an energy excess (as we do – more energy coming in than going out) we will continue to warm and it will virtually all be anthropogenic.

Anyway, I don’t know if I’ve quite explained that as clearly as I would have liked, but the post was really just an excuse to post the video showing Kevin Trenberth discussing a possible El Niño event later this year 🙂

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12 Responses to On the coming El Nino

  1. uknowispeaksense says:

    Reblogged this on uknowispeaksense.

  2. John says:

    Reblogged this on jpratt27.

  3. Eli Rabett says:

    Patience is a virtue. The whole thing is weird. El Nino, melting of the Artic, etc, are not things to wish for, but the horse shit is so deep you almost want these things to happen to to shut the fools up and get people to pay attention. Sucks to be human. . . . Wait.

  4. AnOilMan says:

    How long until we hear, “It hasn’t warmed since 2014!” (Or will it be 2015?)

  5. dhogaza says:

    AOM – 2015 …

    Gives them nearly a year to fine-tune their bullshit.

  6. AnOilMan says:

    Just a thought, but why wait? Why can’t we write it for them now. You know… post date it and all that. I mean, we know what they will say. Its not like there is a mystery about this.

  7. Andrew Dodds says:

    Hmmm. Interesting thought experiment.. how fast would we have to increase climate forcings to ensure that at least 95% of years were warmer than the previous.(as measured by surface temperatures).

    Best keep it a thought experiment.

  8. Hans Erren says:

    Eli, good you mention horse manure: If the horse manure trend of 1914 is extrapolated to the present, the average height of horse manure in the streets would be 50 cm – 100 cm. So be very careful with extrapolating CO2 trends a hundred years into the future.

  9. Hans,

    So be very careful with extrapolating CO2 trends a hundred years into the future.

    Except we have control over this. We certainly determine how much is emitted, and unless the sinks start to behave very strangely, we can use what we will emit under various scenarios to estimate how the atmospheric concentration will change.

  10. verytallguy says:

    Hans,

    the point might be that the horse manure people were right – growth in horse numbers was unsustainable.

    Likewise, Co2 growth is unsustainable. The only questions are how, and when, it will reduce.

    It does not follow that the consequences of allowing that reduction to be uncontrolled will be benign or positive.

  11. Pingback: Another Week of Climate Disruption News, May 4, 2014 – A Few Things Ill Considered

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