List and ccs
Thanks to both Mike and John.
I think John is closer to my question (in talking about horizontal
flows and forestry) on how this whole topic might impact different aspects of
geoengineering. Especially because so much of this list’s dialog has revolved
around precipitation - and because of this paper’s claim that present modeling
is missing an important physical principle. True or not?
As I read this and several other papers by these authors, I found
little use of the word “clouds” - which clearly is still an important topic for
modelers. Is there a cloud message somewhere in here?
I have included Drs. Makarieva and Shiel this time to see if they have
given thought to geoengineering impacts of this paper (or any other of their
many related to climate topics). Dr. Shiel is important as an English
speaking co-author and a forestry expert.
My two questions here are what is the impact of this paper/topic for
geoengineering and why there has been so much (welcome) emphasis on forests.
Should we be paying more attention to water availability and drought mitigation
on this list?
Ron
On Jun 1, 2015, at 6:35 PM, Mike MacCracken <[email protected]> wrote:
> Hi John—I am not sure one can separate then. For example, where one has a
> thin boundary layer and then the free atmosphere above, it is like having two
> different fluids that don’t mix all that well, so if far inland one gets
> convection pulling the lower layer in with a horizontal gradient, so
> resolution can matter in the vertical to maintain the distinction of the two
> layers, allow wave, etc. AS I said before I am not sure one can really
> separate the two aspects.
>
> Best, Mike
>
>
> On 6/1/15, 8:16 PM, "John Harte" <[email protected]> wrote:
>
>> I'm not a climate modeler and my understanding of what goes in to
>> conventional physics process-based atmospheric models is very limited, so
>> correct me if I am wrong mike, but I was under the impression that it was
>> the horizontal not the vertical pressure gradients that M & G think is
>> inadequately treated in conventional models. Isn't it those horizontal
>> pressure forces that power their biotic pump.
>>
>> At least in the context of the Amazon, I would like to see a back of the
>> envelope comparison of the pressure forces driven by condensation and the
>> larger-scale forces that power the trade winds.
>>
>>
>>
>>
>> John Harte
>> Professor of Ecosystem Sciences
>> ERG/ESPM
>> 310 Barrows Hall
>> University of California
>> Berkeley, CA 94720 USA
>> [email protected]
>>
>>
>>
>> On Jun 1, 2015, at 4:56 PM, Mike MacCracken <[email protected]> wrote:
>>
>>> Re: [geo] Smart reforestation must go beyond carbon: expert | CIFOR Forests
>>> News Blog
>>> Hi Ronal, Brian, John, et al.—As a modeler, I would imagine the question is
>>> just what is it that one would want added to the models. Quite a number of
>>> skeptics want the models to add in long cycles evident in the
>>> observations—that would be fine in empirical models, but the whole idea of
>>> physical models (i.e., models based on the physics, chemistry, etc.--but
>>> process based on physical principles, etc.) is not to put in arbitrary
>>> items for which there is not a physical process.
>>>
>>> So, for this forest case, what might this be? Well, having finer resolution
>>> would likely help and as one goes down to relatively fine resolution the
>>> hydrostatic assumption enforced by the formulation of the equations in
>>> these models needs to be adjusted so that non-hydrostatic influences can be
>>> included (i.e., so that the models can treat the vertical acceleration of
>>> the winds). Whether that would help in the simulations I have no real idea
>>> or experience.
>>>
>>> Another reason for going to finer resolution is to better represent
>>> orographic features, and this might be a contributing factor. There is also
>>> an aspect of doing this that I have been suggesting needs to be included.
>>> For those who remember flying into Los Angeles and seeing thin, elevated
>>> levels of pollution during the descent, it took a while to understand what
>>> was causing these (it was not formation and reformation of the inversion,
>>> for example). What a UCLA meteorology professor named James Eddinger, as I
>>> recall, found was that in the afternoon when the Sun was shining on
>>> hillsides facing to the southwest thin layers of air could rise along the
>>> heated slope, and the heating of the air would compensate the adiabatic
>>> cooling, so the air parcel would keep rising into the inversion. This
>>> continued until the air reached the top of the mountain and so ran out of
>>> the surface heating. At this point, the polluted air, having started in the
>>> marine boundary layer, could neither rise further through the inversion nor
>>> sink due to its warmth, so it spread out at its density in the inversion,
>>> forming widely spread thin layer at the altitude of the mountain.
>>>
>>> I have been suggesting there are at least two other examples of this
>>> happening (i.e., of low level air being carried up the sun-heated slopes of
>>> mountain sides that faced the afternoon sun position). One likely place
>>> would seem to be India and the Himalayas—in the region, the polluted air is
>>> of order 9K meters high or so—how could moist polluted air get to that
>>> altitude; I‘d suggest only by hot mountainsides in the Himalayas carrying
>>> such air upward, keeping it warm so that it does not cool and precipitate
>>> out the particulate matter. The second is the late afternoon mountain top
>>> precipitation that occurs along Mexico’s Pacific coast mountain ridge; the
>>> whole area is under an intense anticyclone, so very dry air and a strong
>>> inversion, and yet there is precipitation at the top of the mountains in
>>> the late afternoon—so, I’d suggest that most marine air is rises along the
>>> heated, southwestward facing mountain slopes in the afternoon until it
>>> reaches the mountaintop, where it can cool and so condensation occurs,
>>> leading to the misty precipitation in what would otherwise be a very dry
>>> air mass.
>>>
>>> The global models really don’t represent this—their resolution is too
>>> coarse and their vertical layering is generally more box-shaped than sloped
>>> (use of the sigma vertical coordinate system could technically handle this
>>> if resolution fine enough). I had encouraged a modeler experienced with
>>> finite element models to do some schematic tests of the idea, but, being
>>> retired, no way to really push for that to get done on someone’s extra time
>>> (if you know someone who could do it, student or prof, I’d be happy to go
>>> into a bit more detail). Whether this might have anything to do with the
>>> Amazon situation I don’t know.
>>>
>>> Another general problem with the climate models has been not having fine
>>> enough resolution to really do the boundary layer very well—having to
>>> retain strong vertical layering an be pretty difficult to do. So, again,
>>> resolution may be an issue.
>>>
>>> And then there is the issue of the CCN loadings and sources and types, etc.
>>>
>>> So, indeed, there could be model problems, but to fix them in such models
>>> one needs to focus on getting the physics right, not introduce arbitrary
>>> empirical observations—those are what we need to evaluate the
>>> representations of the physics.
>>>
>>> Best, Mike
>>>
>>>
>>> On 6/1/15, 7:05 PM, "Ronal W. Larson" <[email protected]
>>> <x-msg://1239/[email protected]> > wrote:
>>>
>>>> List, especially Mike and John, cc Brian (who started this)
>>>>
>>>> 1. This is to explore further how this biotic pump topic would influence
>>>> any part of geoengineering. I have concluded, like Brian, that this
>>>> paper is important in promoting regrowth of forests. John certainly
>>>> agrees and probably (?) Mike. Anyone disagree?
>>>>
>>>> 2. Inadvertently (I thought this was a 2015 paper for a while), I read
>>>> not only the final paper, but the many difficulties in getting it
>>>> published (> 1000 days). From the 24 subsequent papers found through
>>>> Google Scholar, I conclude that it is not now a continuing controversy -
>>>> but I have found no evidence that the paper has changed any existing
>>>> models (as I’m sure the authors intended and hoped). Anyone know?
>>>>
>>>> 3. Others may find it interesting to see how the controversy was handled.
>>>> Although it took a long time, I think the Journal basically did a good
>>>> job and made a correct (but controversial) decision to publish. I was
>>>> surprised how all (?) the editorial review correspondence is still
>>>> available (nothing anonymous) - at a site given by the main editor in the
>>>> paper’s last paragraph.
>>>> The main author, Dr. Makarieva, was indefatigable - many dozens of pages
>>>> defending everything in the paper. Here is the summary (with
>>>> forest-oriented emphases added) from her invited post-publication comment
>>>> at:
>>>>
>>>> http://judithcurry.com/2013/01/31/condensation-driven-winds-an-update-new-version/#comment-291429
>>>> Summary and outlook
>>>> The Editor’s comment on our paper ends with a call to further evaluate our
>>>> proposals. We second this call. The reason we wrote this paper was to
>>>> ensure it entered the main-stream and gained recognition. For us the key
>>>> implication of our theory is the major importance of vegetation cover in
>>>> sustaining regional climates. If condensation drives atmospheric
>>>> circulation as we claim, then forests determine much of the Earth’s
>>>> hydrological cycle (see here <http://www.bioticregulation.ru/pump> for
>>>> details). Forest cover is crucial for the terrestrial biosphere and the
>>>> well-being of many millions of people. If you acknowledge, as the editors
>>>> of ACP have, any chance – however large or small – that our proposals are
>>>> correct, then we hope you concede that there is some urgency that these
>>>> ideas gain clear objective assessment from those best placed to assess
>>>> them.
>>>>
>>>> 4. A slightly later paper entitled “Revisiting forest impact on
>>>> atmospheric water vapor transport and precipitation”, by many of the same
>>>> authors is also NOT behind a paywall - and carries this forest theme
>>>> further: http://www.bioticregulation.ru/common/pdf/taac-en.pdf. There
>>>> are numerous other climate related papers from this Russian group - that
>>>> almost certainly have relevance also on the SRM side of “Geo”.
>>>>
>>>> Ron
>>>>
>>>>
>>>> On May 31, 2015, at 11:02 AM, Mike MacCracken <[email protected]
>>>> <x-msg://1239/[email protected]> > wrote:
>>>>
>>>>> Re: [geo] Re: Smart reforestation must go beyond carbon: expert | CIFOR
>>>>> Forests News Blog
>>>>> How are they not both important—the condensation releases the heat that
>>>>> carries the air upward, creating a pressure gradient that pulls the air
>>>>> ashore?
>>>>>
>>>>> Mike
>>>>>
>>>>>
>>>>> On 5/31/15, 10:09 AM, "John Harte" <[email protected]
>>>>> <x-msg://1239/[email protected]> <x-msg://153/[email protected]
>>>>> <x-msg://153/[email protected]> > > wrote:
>>>>>
>>>>>> The work of Makarieva and Gorshkov (note: not Gorshkov and Makarieva;
>>>>>> she is first author on their papers on this topic) is challenging
>>>>>> atmospheric scientists not because it points to the huge role of forests
>>>>>> in the hydrocycle (I have been teaching that for decades) but rather the
>>>>>> specific mechanism they propose. Their argument is that it is the
>>>>>> pressure difference created by condensation, not the heat released by
>>>>>> condensation, that is the more important driver. Certainly both play a
>>>>>> big role; my understanding is that the pressure effect was largely
>>>>>> ignored in the past.
>>>>>>
>>>>>> John Harte
>>>>>> Professor of Ecosystem Sciences
>>>>>> ERG/ESPM
>>>>>> 310 Barrows Hall
>>>>>> University of California
>>>>>> Berkeley, CA 94720 USA
>>>>>> [email protected] <x-msg://1239/[email protected]>
>>>>>> <x-msg://153/[email protected] <x-msg://153/[email protected]> >
>>>>>>
>>>>>>
>>>>>>
>>>>>> On May 30, 2015, at 2:49 PM, Brian Cartwright
>>>>>> <[email protected] <x-msg://1239/[email protected]>
>>>>>> <x-msg://153/[email protected]
>>>>>> <x-msg://153/[email protected]> > > wrote:
>>>>>>
>>>>>>> To the geoengineering group,
>>>>>>>
>>>>>>> I'm curious whether group members are familiar with the "biotic pump"
>>>>>>> model of Gorshkov and Makarieva; this article gives a quick
>>>>>>> introduction:
>>>>>>>
>>>>>>> http://news.mongabay.com/2013/0130-hance-physics-biotic-pump.html
>>>>>>>
>>>>>>> A big climate benefit of inland forests is that phase change from
>>>>>>> evapotranspiration -> condensation creates low-pressure areas that pull
>>>>>>> in moisture and create healthy weather circulation. Seems to me that
>>>>>>> widespread deforestation is aggravating stalled hot-weather trends by
>>>>>>> blocking this kind of circulation. The leaf area of a mature forest
>>>>>>> offers considerably more surface area for evaporation than the same
>>>>>>> area of open water on ocean or inland lake.
>>>>>>>
>>>>>>> Brian Cartwright
>>
>>
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