Comments jshore has made

  • Implications on climate sensitivity not so clear

    The actual scientific article, by the way, appears to be freely available on the journal website: http://www.nature.com/ngeo/journal/vaop/ncurrent/full/nge ...

    One of the impressions that I get from reading the paper is that the implications for climate sensitivity are not so clear.  People here have been assuming that, by adding BC to the positive forcings column and considering the warming all the forcings have produced thus far, you are implying a lower climate sensitivity.  However, what the authors seem to imply is that they are not so much claiming that the total aerosol forcing is now less negative but rather that they think the total is about right but that the distribution among the components is different.  I.e., black carbon has a stronger positive forcing while the non-BC aerosols have a somewhat stronger negative forcing to compensate.  

    This would also agree with a basic conception I had that the best constraints on the total aerosol forcing were actually from "inverse studies" that tried to see what patterns of effects it was having rather than by direct calculations of what its effect should be.  

    It is also worth noting that because of the large error bars associated with the total aerosol forcing, as well as other issues (such as uncertainties in solar forcing, ...), climate sensitivity estimates have never been very well-constrained by looking at the warming over the last century.  Better constraints have been obtained by other methods (e.g., from climate models themselves, from events further back in history like the ice age - interglacial transition, and from studies of the climate effects of the Mt. Pinatubo eruption.  (Of course, the latter involves aerosol emissions...although I think the important effects are from the ones that make it into the stratosphere where they hang around longer and I would presume that these behave somewhat differently than aerosols in the troposphere.)On New study: Ordinary soot second biggest driver of climate change posted 1 year, 8 months ago 14 Responses

  • cbrtxus,

    You say: "Anyone who wants to do even rudimentary research on the Internet will find that statement to be at best misleading."

    Well, if you do your research on the internet, you would probably also conclude that there is no consensus on the correctness of evolutionary theory.  The point is that one has to look in the peer-reviewed scientific literature to see what, if any consensus exists, and there one finds there is a strong consensus.  This doesn't mean there are no other opinions, as Coby notes, but they are a small minority.  

    One can never expect unanimous agreement.  For example, Fred Singer is not going to stop claiming that AGW is a non-issue.  He is perfectly happy to spend years arguing that the satellite record shows little or no warming...and then turn on a dime when this claim becomes untenable, and immediately switch to the claim that the warming is part of an "unstoppable" 1470 year (natural) cycle.  How can you hope to convince such a person?

    I think when the scientist who is probably the most respected of the climate change deniers, Richard Lindzen, starts publicly making statements so deceitful as the claim that there has been no warming since 1998 then it is clear that the real scientific debate is long over.  If Lindzen had real scientific arguments to make, he wouldn't be reduced to the claim that is equivalent to a statement like "Today in Rochester it was warmer than it was last Saturday.  Therefore, this unproven idea of seasons, and that we are currently heading toward winter, is unfounded."On 'There is no consensus'--If this is not consensus, what would consensus look like? posted 3 years ago 109 Responses

  • Christy's comment not surprising

    In reading that comment from Christy, you have to remember the history:  He and his colleague Roy Spencer are the ones whose original analysis of the temperature of the troposphere measured by satellites showed slight cooling...until, over the years, they implemented variations corrections that others pointed out had to be made to the data...until it has now come mainly into agreement with the surface record (although other groups analyzing the satellite data independently get still more warming and better agreement).

    During this whole process, it has been clear that both Spencer and Christy were strong skeptics on climate change...and certainly not without political biases too.  In fact, Spencer now writes a column for the libertarian Tech Central Station in which, in addition to expressing his skepticism about the importance (if not the reality) of global warming, he even recently gave a ringing endorsement for Intelligent Design in a column ( http://www.tcsdaily.com/article.aspx?id=080805I ) entitled "Faith-Based Evolution"!  Needless to say, this ain't gonna help him to not look a bit wacko to the rest of the scientific community!

    So, this is just a long-winded way of saying that a statement like that coming from Christy ought to be considered a fair bit of progress given where these guys have been coming from.On If it walks like a duck and talks like a duck ... posted 3 years, 7 months ago 8 Responses

  • Great summary!

    I think you hit the nail on the head with what the larger lesson from Katrina is.

    And, similarly with your point about ANWR...Indeed, the symbolic stakes are high.  It is not so much this particular place but what it represents particularly in terms of whether we are going to continue to coddle to our fossil fuel addiction or whether we will instead deal with energy issues in a more comprehensive way that recognizes the connection with climate change, etc.On Chock full of good news ... ha ha ... posted 3 years, 10 months ago 8 Responses

  • DDT History

    While I agree with Kristof's conclusion that DDT should be used for indoor spraying to fight malaria where it is effective, I think he may have bought into a little too much of the history of DDT according to Milloy, Crichton, et al.  There is a whole other side of the story that he didn't cover which is how the unbridled use of DDT, particularly in agriculture, led to the buildup of resistance to it, thus rendering it ineffective in some places in the fight against malaria.  Here is a nice discussion of this.  The 1981 Nature paper cited there is particularly interested as it shows data for India in the 1970s when malaria deaths were positively exploding while DDT use (apparently largely in agriculture) was increasing.
    On The North knows best? posted 4 years, 10 months ago 19 Responses