Ocean Circulation Doesn't Work As Expected 658
techno-vampire writes with word that a long-accepted model of deep ocean currents is inaccurate. Deep Sea News has a summary of the research, to be published in Nature. The Woods Hole press release has more details. "A 50-year-old model of global thermohaline circulation that predicts a deep Atlantic counter current below the Gulf Stream is now formally called into question by an armada of subsurface RAFOS floats drifting 700 - 1500m deep. Nearly 80% of the RAFOS floats escaped the Deep Western Boundary Current (DWBC), drifting into the open ocean. This confirms suspicions that have been around since the 1990s, and likely plays havoc with global models of climate change."
"long accepted" (Score:4, Informative)
Re:deniers come out in 3 .. 2 .. 1 .. (Score:3, Informative)
and since no conveyor means no warm gulf steam to warm the northeastern US and European continents, they will get colder.
Does the Gulf Stream actually have much of an impact on North America? Wouldn't the typical weather patterns (i.e: west to east) suggest that the heat moved by the Gulf Stream would wind up making most of it's impact on the Atlantic Ocean and Europe?
I love science (Score:5, Informative)
Damnit, I love science!
This is how it's supposed to work.
Doesn't contradict global warming (Score:5, Informative)
These results don't say that global warming is occurring. In fact, they neither support nor oppose the idea at all. The Woods Hole press release [eurekalert.org] is fairly neutral:
"May impact the work of global warming forecasters" is true; it might also influence the thinking of UFO chasers but that won't help determine whether they're piloted by little green men. This research will complicate models designed to model the specific effects of global warming. Given how much is unknown yet, and how much has yet to be determined by human activities (to the extent that we choose to mitigate or fail to mitigate our impact on the biosphere) those models are already only potentially correct by marvelous coincidence anyway.
Um, not quite. (Score:5, Informative)
IAAPO (physical oceanographer).
The quoted blog is being a little over-excited about this. There's nothing in WHOI's press release that suggests that this brings the thermohaline circulation tumbling down, and certainly nothing to play "havoc" with climate models. Quoth the press release:
And since this cold southward-flowing water is thought to influence and perhaps moderate human-caused climate change, this finding may impact the work of global warming forecasters.
"This finding means it is going to be more difficult to measure climate signals in the deep ocean," Lozier said. "We thought we could just measure them in the Deep Western Boundary Current, but we really can't."
In other words, the circulation is there, but it's more diffuse that expected, and so you can measure it by looking at a well-defined path along the continental shelf as expected. That requires some revamping of theory, and will make circulation model validation and data assimilation more difficult, but that's all.
The DWBC has an interesting scientific history -- it's one of the few ocean phenomena predicted by theory before it was observed, in part because its depth and slowness prevented observation.
But, hey, never mind, Al Gore, manbearpig, lalala I can't hear you.
Re:deniers come out in 3 .. 2 .. 1 .. (Score:4, Informative)
That may be true now, but it used to be science, a long time ago, back in the 1990s, back when only journals and magazines such as Science or Nature would talk about it and that no one else cared or listened. I grew up in the 1990s in France reading Science & Vie, global warming was there all along, back then we called it 'climate warming', but then suddenly the American public started caring, and that's when the shit went down and it all became controversial and hysterical.
You damn kids and your newfangled climatological hysteria, get off my lawn!
Re:Darn it (Score:5, Informative)
And I already replaced all my light bulbs with those dim, mercury-filled corkscrew kind!
Dim? The lower energy usage and heat output means I can put "100 Watt equivalent" bulbs in fixtures that are only supposed to have 60 Watt bulbs in them, that's quite a bit brighter. Plus they don't have that horrid long-wavelength tinge to them.
I can't be the only one that hates those damn things. They are useful in areas where the lights are left on for extended periods but I find them to be highly annoying in areas that I walk into and out of quickly. They don't even manage to reach full brightness before I've accomplished what I came into the room to do.
Most of he ones I have hit full brightness pretty much immediately. The ones that do take a while are "floodlight" shape and can go in enclosed spaces without getting fried, don't know whether they're just crappy or starting quickly isn't compatible with surviving that.
Re:deniers come out in 3 .. 2 .. 1 .. (Score:5, Informative)
There are two separate issues here. On the one hand there are certainly serious scientists working on climatology and climate change. I have no doubt they will incorporate the new information and work to improve their models. However, they are also much more careful about their certainty of the future, than...
The other side of the debate, which is political; it deals with what policies (if any) should be put in place to combat climate change. And in this realm, we are being bombarded by "it's settled science", "it's going to happen", "we have to act in ten years or it'll be too late", etc. ad inf. And the unseriousness of these positions is made clear by radical flaws in models such as the one referenced in this article.
Re:The global (computer) models of climate change (Score:2, Informative)
This is slashdot so I'll just assume you didn't RTFA. Here's the original article:
http://www.sciencedaily.com/releases/2009/05/090513130942.htm
In summary, this finding just makes it harder to measure the effects of climate change. No where does it invalidate climate change you dumb ass. Instead of just measuring the cold return current as they previously thought, the water takes a diffuse route back to the tropics.
Re:Darn it (Score:1, Informative)
Most CFLs instantly turn on to about 70% of the rated brightness and take a couple of minutes to reach 100%. However, since they use less than a quarter of the electricity and produce much less heat, you can use a CFL which is rated as 50% brighter than the incandescent it replaces. That results in instant 1.5*0.7=105% brightness and 150% brightness after a couple of minutes, while still using less than a third of the electricity.
Also, get your electrical installation fixed.
Bad Title, Bad Summary, Bad Article (Score:5, Informative)
I am a nature subscriber and I just read the letter which this crap is 'based on'. In what I find to be depressing regularity the content in Nature Magazine is misrepresented. Presumably because some of the content at Nature.com is only available to subscribers.
So the title of Slashdot submission is wrong. The summary and free article at deepseanews it is based on mischaracterize the content of the letter. And naturally most of the comments here on Slashdot don't take into account the article, the letter, or anything that smells to much like reality.
If anyone is particularly interested the study found additional new details about ocean currents which the suggest should be included in future model of global ocean currents. This isn't especially exciting but I suppose it's interesting from a point of view of making our understanding and models more complete.
So nothing there about ocean circulation not working the way scientists have described (or a "a major paradigm shift in ocean circulation theory.") Nothing there about failure of models. Nothing there about climate change being either true / not true or stronger / weaker.
This is just what most science is all about... making current understanding more complete or more correct. Below is the excerpt, which I believe to be publication available.
To understand how our global climate will change in response to natural and anthropogenic forcing, it is essential to determine how quickly and by what pathways climate change signals are transported throughout the global ocean, a vast reservoir for heat and carbon dioxide. Labrador Sea Water (LSW), formed by open ocean convection in the subpolar North Atlantic, is a particularly sensitive indicator of climate change on interannual to decadal timescales1, 2, 3. Hydrographic observations made anywhere along the western boundary of the North Atlantic reveal a core of LSW at intermediate depths advected southward within the Deep Western Boundary Current (DWBC)4, 5, 6, 7, 8, 9. These observations have led to the widely held view that the DWBC is the dominant pathway for the export of LSW from its formation site in the northern North Atlantic towards the Equator10, 11. Here we show that most of the recently ventilated LSW entering the subtropics follows interior, not DWBC, pathways. The interior pathways are revealed by trajectories of subsurface RAFOS floats released during the period 2003â"2005 that recorded once-daily temperature, pressure and acoustically determined position for two years, and by model-simulated 'e-floats' released in the subpolar DWBC. The evidence points to a few specific locations around the Grand Banks where LSW is most often injected into the interior. These results have implications for deep ocean ventilation and suggest that the interior subtropical gyre should not be ignored when considering the Atlantic meridional overturning circulation.
Re:deniers come out in 3 .. 2 .. 1 .. (Score:4, Informative)
Uh, does the guy who opens the flood gates at the dam 'create' the water that flows out of it? not hardly. But that doesn't diminish the effects of LOTS more water downstream does it?
Humans have clearly and measurably increased the carbon dioxide in the ATMOSHPHERE. That comes from burning MILLIONS of years of carbon sequestered in the oil. This is the problem and the 'unnatural' influx of which I spoke. it would not have happened this much this fast without us actively digging it up and burning it.
As for the other sources of heat you mention, the solar aspects are the most reasonable to affect global temperatures since its the basis for just about all life in the first place
However, global warming is not because we are producing more heat than the earth can handle. It is because we are retarding the rate at which it sheds heat into space. How much heat we as a species produce is probably actually pretty measurable as is the amount of heat added by the Sun (Sun heated asphalt would be in our bucket not the Suns). I'd be willing to bet we don't hold a candle to the Sun in that department.
But generally those wonderful thermodynamics laws really do prevent us from 'increasing' the heat on the planet. The rate at which it moves (into space) however is something we can and have readily affected. That's where the vast majority of 'extra' heat is coming from. Without the extra CO2 blanket, transfer rates would simply go up in response to any larger heat concentrations we've caused, still reaching a reasonable equilibrium.
But as you say, by paving over fields and forests, and then reducing the rate at which the extra heat can leave (through processes producing yet more heat) we aren't helping ourselves.
The main problem is still the 'greenhouse' effect.
Re:deniers come out in 3 .. 2 .. 1 .. (Score:3, Informative)
So the conveyor belt may act as somewhat of a coarse 'brake' on global warming over longer time frames.
We have the problem of warming temps melting more ice. This means less salty northern waters. As such the 'conveyor' stops running (based on previous theories). This stops the transfer of heat from the tropics to the northern climates which in turn causes a cooling of the northern climates producing more ice. It is indeed a cyclical process so point A leads to point B to point C and back to A in a massive generalization.
My point was that if the conveyor theory is wrong, the 'brake' I described might not exist or only work at a reduced rate, thus allowing more effect from global warming to be experienced.
Re:Driving Blind (Score:5, Informative)
There's another word for "thawed tundra". It's "bogland", a state it already achieves for a couple months each summer, rendering it impassable to surface vehicles.
Re:The global (computer) models of climate change (Score:4, Informative)
I am not a scientist, but I know that you can us eNewtonian mechanics to figure out where a planet is going to be on any given date time. But if ylou want to slide a satellite into orbit around that planet you need to bust out Einstein. I'm guessing it might be something similar in that this doesn't affect the general trend, but it will change the rate of the trend.
Re:deniers come out in 3 .. 2 .. 1 .. (Score:3, Informative)
I think you've got the wrong idea.
The Stern Review [wikipedia.org] came to the conclusion that the benefits of strong, early action on climate change considerably outweigh the costs.
Waiting fifty years might be the worst thing we could do.
Re:Driving Blind (Score:3, Informative)
Lacrosse is more fun than hockey.
bzzt....wrong (Score:3, Informative)
"The 25 watt CFL you are discussing actually uses 50 watts total power. 25 watts at the bulb, and another 25 at the power company as they try to balance the reactive load."
Please read up on your electronics. It doesn't "use" another 25 watts at the power company. At the most, it uses a very little bit of power due to the extra current flowing in the transmission lines. Maybe a watt or two. This has been discussed here before.
Re:Bad Title, Bad Summary, Bad Article (Score:2, Informative)
If only open access publishing would become more commonplace. Then everyone could see the original article and actually make their own minds up.
Even now it would be nice if they at least linked to the freely available abstract [nature.com].
Re:The global (computer) models of climate change (Score:4, Informative)
Because the warming has been observed. The problem of the ocean currents summarized here is not one of causative mechanism, but of energy transfer. In other words, this is more about the pattern of global warming, not the existence of it.
Re:Driving Blind (Score:2, Informative)
All the topsoil on the canadian shield (the center parts of canada n. of where they grow grain now) pretty much got tossed south during glaciation. That's poor farmland, and acidic even where there's significant soil. It isn't trading one great plains for another, it's trading the great plains for a wasteland. Getting it warmer won't help this land not suck for crops.