On the recovery from the Little Ice Age

CriticalBill wrote: I have two questions
1. Are scientists ever wrong?
2. Are there any pieces of current or future evidence that could make hard core man made climate change believers change their mind and accept that people have little to no significant influence on the climate? What evidence would be needed or are scientists much like religious zealots who will accept nothing but their set-in-stone beliefs?

I have more than 2 answers (are you surprised?!)
1. Yes.
2. I'm breaking your 2 questions up for my reply.
a. There hasn't been any research published that has introduced any uncertainty that the current climate change is not caused by us. There are still gaps in the understanding of climate on regional scales, and of paleoclimate data, and absolutely all factors that influence climate are not understood completely, but there is no doubt that the recent warming trend is being caused by the rapid increase in greenhouse gases in the atmosphere, which can be traced by isotope directly to fossil fuels being burned, and is exacerbated by large-scale deforestation.

b. If there were research published that could realistically explain the current observations of the warming of the atmosphere and oceans, acidification of the oceans, and migration of species then it could not be ignored. Resisted and marginalized at first, as most non-mainstream ideas are, but mounting evidence silences even the most vocal critics. As of yet, after 100+ years studying climate more and more in-depth, no realistic hypothesis has been put forth that would negate anthropogenic global warming.

To counter AGW, I figure it would take a reversal of (and shown in peer-reviewed published papers):
a. warming temperatures of upper levels of oceans (lower levels aren’t measured accurately on a continuous, global level yet) and lower atmospheres despite continued carbon emissions
b. melting glaciers/continents and sea ice
c. plants and animals retreating back into their previously known habitats/latitudes/areas
d. acidification of oceans
2. Evidence and explanation of a previously unknown mechanism affecting climate that robustly explains the warming that we’ve seen to this point that negates or reduces the role of increasing greenhouse gas levels.


There was a News Focus article published recently in Science describing the evolution of views held about Homo sapiens and how they interacted with other hominid species with which they co-existed. This is completely unrelated to climate science, but as I was reading it, I thought to myself that it highlighted perfectly how science works; how hypotheses are formed, investigated, and discarded as new evidence comes to light.
http://www.sciencemag.org/content/331/6016/392.full
A New View Of the Birth of Homo sapiens
Science 28 January 2011: Vol. 331 no. 6016 pp. 392-394
DOI: 10.1126/science.331.6016.392
* News Focus Anthropology
1. Ann Gibbons

Anthropologists have had 2 major competing ideas about how we interacted with Neandertals and other sub-species of our hominid line as we migrated out of Africa. The first view held that we replaced other species (descendants of the Homo erectus line, for example) as we encountered them and the second view held that our ancestors interbred with other sub-species as we migrated and thus formed the Homo sapien line. Recent genome sequencing of Neandertal bones and other hominids has shown definitively that there was interbreeding occurring, completely negating the 1st hypothesis, although not proving interbreeding to the extent that the original 2nd hypothesis claimed. The truth most assuredly lies somewhere in the middle, that a significant portion of our ancestors interbred with other hominid species and incorporated some of the DNA into our line, and we've obviously "replaced" them as they don't exist as separate species today (they exist inside us as their descendants, as part of them can be identified by unique genetic sequence in us, so they aren't truly replaced, just modified greatly). One of the main proponents of the first hypothesis, that we merely replaced earlier species without interbreeding, has had to modify his hypothesis in the face of this evidence. When it's your life work, it can be hard, but to not do so means facing irrelevance, ridicule, and eventually, a lack of funding. Stubbornly clinging to debunked ideas will get them nowhere.

Science can be funny. We don't yet have the mental capacity to figure it all out in great leaps - it takes small steps, and often mis-steps, to gain the bigger picture understanding. Fifteen years ago, few would've claimed that we contain Neandertal genes within us, and thus interbred - we imagined history so much neater - that we moved into Europe and the Neandertals just died the next day, essentially, ceding dominion to us. Life is so much more messy. And when the tools aren't available yet to prove that early humans mated with Neandertals, and had viable offspring, then it's hard to get anyone to listen to that crazy-sounding idea. But when you stop to think about it, it makes sense that it would've happened that way, and now the evidence supports that notion and the search for what really happened continues.

After all, the dinosaurs didn't die out, they live among us today in their descendants...they just look a whole lot different.

I'm not saying I know any answers just as I have no clue how we were somehow created (or evolved) from nothing.

So, we didn't come from nothing, but the method by which we did come about will remain unanswered for a long time to come, and it may or may not come from science.

residenttroll wrote: I am starting to think the climate change graphs are just Al Gore erection measurements during his massages.

RT, I would love, love, love it if you would add your constructive arguments (you can't say I didn't warn you well enough in advance to get up to speed on your global warming info!) rather than just your humorous distractions. Muchas gracias!

lionshead2010 wrote: I had a chance to take introductory level meteorology and oceanography courses not too long ago and was fascinated by the connection between the Earth's prevailing winds and predicatable ocean currents.

As I recall, ocean currents are driven, at least in part, by the salinity of the sea and density issues (I'm no oceanographer).....so as the ice caps melt (either through man-made or natural causes) can we expect a change in ocean currents and prevailing winds? I would think so.

Yes, that's what I've read too. Wally Broecker's book, The Great Ocean Conveyor, was a great intro to that subject - he's been studying it since the 50's. http://www.amazon.com/Great-Ocean-Conve ... 0691143544

I wonder what winter looks like in a place like the British Isles and Northern Europe if you alter the warming ocean currents that moderate their climate? I wonder if increased growing seasons in the northern climates will impact the ability of farmers in those regions to grow certain crops? How will the change in prevailing winds impact precipitation patterns....and how does that impact agriculture? I don't expect anyone to answer these question but the potential answers are mind boggling for those who like to ponder these things.

If I remember right, winters are predicted to get milder, unless the conveyor slows dramatically (that isn't expected to happen anytime soon), then it will be deep-freeze instead. Crops will definitely change - already there's talk of England becoming a great wine-growing region and France losing it's magic. Similarly, here in the US, Napa very well may go to crap, and Oregon and Washington become the premiere regions in several decades. Winds, ENSO, etc will all be affected and in turn affect regions differently, in what direction and to what extent is still largely unknown - improving those regional predictions are a hot item of current research. Too, it depends on how soon public opinion and political will is turned and fossil fuel use and deforestation curbed, as business as usual will increase the severity of effects seen in climate and weather, but mitigation will lessen effects seen. For example, the realization that the ozone hole existed, and subsequent drastic reduction in the use of CFC's which exacerbated it, reduced a good deal of warming that would've occurred had that policy not been implemented world-wide (CFCs are potent GHGs).

What does global climate change REALLY mean to mankind and the many, many other species that roam this earth? That's the answer I seek.

Past abrupt climate changes have usually meant reductions in the total number of species and bottle-necking of species that make it through. Already the number of plants and animals that are going extinct every year is increasing. I'm sure we'll survive, but with a great population reduction and drastic lifestyle change.

This stuff makes shirtless congressmen boring. :VeryScared:

Boring, maybe. To me, irrelevant, irritating, and frustrating that we continue to be so short-sighted and self-destructive as a species.

A few more links to data on ocean circulation (to counter any bias I may be introducing, anyone is free to go to http://www.ncbi.nlm.nih.gov/ and search PubMed for ocean circulation, ocean conveyor, or any other variation of that term and check out all the hits that come back - these first four seemed most relevant/comprehensive/informative to me - I like reviews):

http://www.ncbi.nlm.nih.gov/pubmed/21285956
Tracking the Atlantic Multidecadal Oscillation through the last 8,000 years.
Nat Commun. 2011 Feb;2:178.
Knudsen MF, Seidenkrantz MS, Jacobsen BH, Kuijpers A.

The nature and origin of the AMO is uncertain, and it remains unknown whether it represents a persistent periodic driver in the climate system, or merely a transient feature. Here, we show that distinct, ∼55- to 70-year oscillations characterized the North Atlantic ocean-atmosphere variability over the past 8,000 years. We test and reject the hypothesis that this climate oscillation was directly forced by periodic changes in solar activity. We therefore conjecture that a quasi-persistent ∼55- to 70-year AMO, linked to internal ocean-atmosphere variability, existed during large parts of the Holocene. Our analyses further suggest that the coupling from the AMO to regional climate conditions was modulated by orbitally induced shifts in large-scale ocean-atmosphere circulation.

http://www.ncbi.nlm.nih.gov/pubmed/21141656
Paleophysical oceanography with an emphasis on transport rates.
Ann Rev Mar Sci. 2010;2:1-34.
Huybers P, Wunsch C.

Paleophysical oceanography is the study of the behavior of the fluid ocean of the past, with a specific emphasis on its climate implications, leading to a focus on the general circulation. Even if the circulation is not of primary concern, heavy reliance on deep-sea cores for past climate information means that knowledge of the oceanic state when the sediments were laid down is a necessity. Like the modern problem, paleoceanography depends heavily on observations, and central difficulties lie with the very limited data types and coverage that are, and perhaps ever will be, available. An approximate separation can be made into static descriptors of the circulation (e.g., its water-mass properties and volumes) and the more difficult problem of determining transport rates of mass and other properties. Determination of the circulation of the Last Glacial Maximum is used to outline some of the main challenges to progress. Apart from sampling issues, major difficulties lie with physical interpretation of the proxies, transferring core depths to an accurate timescale (the "age-model problem"), and understanding the accuracy of time-stepping oceanic or coupled-climate models when run unconstrained by observations. Despite the existence of many plausible explanatory scenarios, few features of the paleocirculation in any period are yet known with certainty.

http://www.nature.com/news/2010/100912/ ... 0.461.html
Ocean conveyor-belt model stirred up
News: Analysis of temperature and salinity shakes view of global water flow.
Published online 12 September 2010 | Nature | doi:10.1038/news.2010.461
Adam Mann

http://www.sciencemag.org/content/328/5985/1507.full
* Review: Deconstructing the Conveyor Belt
Science 18 June 2010:
Vol. 328 no. 5985 pp. 1507-1511
DOI: 10.1126/science.1189250
M. Susan Lozier

For the past several decades, oceanographers have embraced the dominant paradigm that the ocean’s meridional overturning circulation operates like a conveyor belt, transporting cold waters equatorward at depth and warm waters poleward at the surface. Within this paradigm, the conveyor, driven by changes in deepwater production at high latitudes, moves deep waters and their attendant properties continuously along western boundary currents and returns surface waters unimpeded to deepwater formation sites. A number of studies conducted over the past few years have challenged this paradigm by revealing the vital role of the ocean’s eddy and wind fields in establishing the structure and variability of the ocean’s overturning. Here, we review those studies and discuss how they have collectively changed our view of the simple conveyor-belt model.

IPCC 4th Assessment from 2007: http://www.ipcc.ch/publications_and_dat ... n/ch5.html
Chapter 5: Observations: Oceanic Climate Change and Sea Level

http://www.realclimate.org/index.php/ar ... owdown-no/
Ocean Circulation: New evidence (Yes), slowdown (No)
— gavin @ 31 October 2006

http://www.realclimate.org/index.php/ar ... n-changes/
Atlantic circulation change summary
— gavin @ 19 January 2006
Nature this week has an excellent summary http://www.nature.com/nature/journal/v4 ... 9256a.html of the state of the science with regards to possible changes in the ocean thermohaline (or meridional) circulation in the Atlantic and its impact on climate. Even though it quotes a couple of us, it’s still worth reading if you want to understand how results like the Bryden et al paper – that suggested that the Atlantic overturning had reduced by 30% in recent decades – are assimilated into the scientific picture.


lionshead - where did you take your intro meteorology and oceanography courses? I'd be interested in taking them myself!

It's in the data, go take a look!

My scientists, huh?

Baby, if they were mine, we would've taken over the world already and started fixin' this mess, instead of talking it to death!