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Global warming? I am more worried about global cooling.


Ganoderma

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I can't say that i know a whole lot about the way this thing works but i have been reading that through global warming the sea currents and air currents can change drastically. this could also lead to such disasters as ice ages. this was in teh Royal BC museum in Victoria BC canada, they had a global warming exhibit.

 

Can someone help explain this a little better? i understand how different water/air currents could cool the earth or warm the earth depending. but i dont see how it can cause soemthing like an ice age.

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Not having done any research, I can only repeat what I think I remember. All this information will be biased toward the East Coast of North America and Europe, as I live near the North Atlantic. Because of global warming, the glaciers are melting. Because the glaciers are melting, a lot of fresh water is being pumped into the ocean. This is disrupting the gulf stream, and has already made it noticably weaker (in the range of 80% of what it was just two or three decades ago). All the land along the North Atlantic is warmed by the gulf stream, especially Europe. Consider that Europe is far north of the USA, yet has a comparable climate, and more temperate. If the gulf stream weakened too much, Europe could cool down considerably, possibly rendering it far less habitable.

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Gano, it may help to consider that the ocean currents heat the North Atlantic region. The currents won't actually cool anything, they will just stop warming the area if the current breaks down.

A large enough influx of fresh water will break down the major warming current. In addition to fresh water from melting glaciers, there is also the added fresh water from rivers. As average temperatures increase more water is held in the atmosphere leading to more rain leading to more water being dumped in the oceans from NW Europe. This last bit is from memory, I apologize for not having a specific resource.

 

The lack of the warming current could allow glaciers to grow over the water of the far north atlantic. The question is, will it be too little to balance what we are doing, or will it over balance leading to an ice age, or somewhere in between.

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hmm i see. so its the warm water currents that are stopping the ice caps from spreading towards the equator? seems to make sense.

 

Well, there are not the sole reason the globe isn't covered with ice. They are a contributing factor.

Unfortunately (or perhaps fortunately) the climate is extremely complicated. There is almost nothing (actually, probably nothing) regarding the climate that is simply affected only by one other thing.

This is why I get frustrated with people saying that man's CO2 is the complete cause of global warming.

I also get frustrated at those that point at the poor mistaken people that think the above and say 'see GW can't exist because those people are wrong'.

 

In many parts of nature there seem to be tipping points. Ecological systems can 'bend' quite a bit. But if pushed too far they break. Similar to a tree in the wind, it will bend but if the wind becomes too great it will suddenly snap or get uprooted.

 

The atlantic current has already been measured at only 80% strength, so it is weakening now. We may not see any adverse effects until it gets cut off entirely, or we may see some affects at 75%. More study is needed.

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The gulf current, among other things ,is driven by the thermal gradient between the warm gulf and cold north atlantic, with warm water flowing toward the cooler water.

 

Another potential is water density. Fresh water is less dense than salt water and will float on the top until it mixes in. Before we had warm-slightly less dense water from the equator flowing toward cold-denser water in the north atlantic, sort of two potentials. Now we have the same warm-less dense water from the equator flowing toward cold water that now is less dense than it used to be. The result is less potential. Once the melt down is complete and the fresh water mixes in, the stream will being to increase flow once again.

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It is one possible result of global warming.

Over all it is always a cycle, the earth will get along just fine, and most likely will renew itself over and over again (personally I doubt that we will cause a runaway greenhouse afect such as Venus' atmosphere).

The question is do we want to deal with the suffering that goes along with it?

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  • 2 weeks later...

What causes and ends ice ages is not well understood. However, typically ice ages are much longer in duration. As ice covers a larger percentage of the planet more and more light from the sun is reflected back into space. Less warming of the surface occurs and so it feeds the cycle. These feedback loops interact with many other positive or negative feedback loops which give us our climate.

 

There isn't a 'preferred' state of the climate. So just because the glaciers return to their former levels doesn't 'turn off' an ice age. The equilibrium shifts over time. In my opinion, minimizing the affect we have on the climate is the safest course of action.

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Whoaaaa! Guys, Guys.. hold on a minute...

 

Global waming? the earth has warmed a little over the last 100 years around 0.7 C, what's the big deal? - PANIC we're all gonna die! no we're not.

 

I'm in the middle of trying to solve this myself at present, I don't care which way it turns out, I just want the truth. So far though, none of the data I have processed is consistent with claims that man is reponsible.

 

What is clear is that what Governments say (even through their scientists) is to be treated with a pinch of salt at least. I wrote to a GW group and asked them for a source of data they quoted, the reply was "This is the firm opinion of all the scientists in this field, that alone should be sufficient to convince you of it's validity" - that's a paraphrase of the letter long since lost, I duly replied thanking them for their response and asked that if they were to write to me again, perhaps they could print it on soft tissue and thereby be assured I could find some use for it.

 

On the other hand when I approached FOS (friends of science) there was no hesitation, any question you ask they answer, any data you want they will point you to it - they were not trying to 'sell' me anything, when I asked for raw data they put me onto the original source, NOT data or graphs from their own website, Quote (fos reply to request for some data) There is not one source. For Mauna Loa, data can be found on their own website - w^3.mlo.noaa.gov... etc etc (damn 10 posts before I can print a w^3)

 

That cut's no Qudos with me I'll wait till I've finished number crunching. IT's worth a trip to the FOS site to get the alternate climate warming view.

 

Well it's way past my bedtime, matron will be looking for me soon....

 

So, don't wet your pants or jump off a bridge, I say I think the trend will reverse within three to seven years, I cant prove it but then GW freaks can't prove what the weather will be like next year!

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I say I think the trend will reverse within three to seven years, I cant prove it but then GW freaks can't prove what the weather will be like next year!
No, "they" (gosh, "they" are so evil!) can't *prove* what the weather will be like next year.

 

On the other hand though, that's a silly question if you rub two neurons together about the subject.

 

What we're all trying to do is prepare for possible outcomes. There appear to be two viewpoints at play here:

  • There is data that shows a definite trend. The slopes of the data points are increasing monotonically over modestly short time intervals. The conclusion is that we should *look* at what we might do about it.
  • Bah. All data is horse hooey. Statistics tells us that we could hit a long negative run any day. Lets just *assume* that's going to be the case, and more importantly, lets *not* spend any time or money on considering possible actions if that's not the case because its going to be a waste of time if the trends take a 180 degree turn within "three to five years".

So, to a lot of us, it makes sense knowing that there could be a range of outcomes to hedge our bets and determine possible courses of action, rather than assume that the exact opposite of what the data is pointing to is going to be the only outcome.

 

Place your bets,

Buffy

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Whoaaaa! Guys, Guys.. hold on a minute...

 

Global waming? the earth has warmed a little over the last 100 years around 0.7 C, what's the big deal? - PANIC we're all gonna die! no we're not.

 

The only person I have ever heard mention 'we are all gonna die' in response to global warming is Rush Limbaugh when he mocked enviornmentalists. I don't believe anyone believes GW will cause us all to die, where did you get that impression?

 

In a worse case scenario, GW could indirectly cause the death of many humans, and could cause pain and suffering to other humans, as well as economic hardship to many countries, businesses and individuals.

 

As for hard data, here are some sources for your research:

 

http://data.giss.nasa.gov/gistemp/2005/

 

http://www.ncdc.noaa.gov/paleo/globalwarming/paleodata.html

 

Another good summary is http://ipcc-wg1.ucar.edu/wg1/docs/WG1AR4_SPM_PlenaryApproved.pdf

 

As a summary, it doesn't hold the detailed data you are looking for. However, it may give you a good gist of the actual science as opposed to the media's representation of the science.

 

I applaud your desire to get your teeth into the data to see for yourself.

And I do hope you are right and I am wrong (when you said you feel that in 5-7 years we will see a reverse of the trend). However, looking at all the evidence, and the trends, and the fact that co2 stays in the atmosphere for many many years, I don't see what basis you have for such a prediction.

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and even if global warming caused an ice age...all living life is made to addapt lol we will all just have to sleep in more blankets at night and all become naturalists so that our body hair will keep us warm lol just kidding:P

 

COMON GUYS I WANT A HAIR T SHIRT!!!

 

hence...big foot returns:D

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Ok, the "We're all gonna die" is a humerous reference to the Media, in order to sell more copies, they slowly 'up the ante' that is, exagerate the data, We've gone from a few centimeters to some estimates of 50 or more metres in the case of sea level rise. Yes, I know how you will respond to that...

 

The source of most of this talk can be traced back to the IPCC, they produce a Summary for Policy Makers (SPM) - here's where you can find it :-

W^3.ipcc.ch/pub/un/syreng/spm.pdf

 

Now have a look at page 34, the graph of Global surface Temperature.

Looks like it spells doom BUT thre are two vital pieces missing, neither the Medieval warm period nor the mini Ice age appear. The evidence for these periods comes from many sources, tree rings, silt, Ice cores, written records etc. That graph is the whole basis of the case for man made GW.

 

More recently it is suggested that sunspot cycle time more closely follows temperature over a period of about 150 years - that's where I am at now, I have a mass of raw sunspot observations going back to around 1874, ok they are direct observations, written down by amateurs (with no political axe to grind). I also have a mass of temperature data again from rural areas, gathered by amateurs with no axe to grind - at present that's the data I'm into. Initially from this data I see a trend of this temperature rise slowing down - I know it's local stuff and it could be an error to rely on this BUT both datasets (One from Ireland and one from Scandinavia) show the same general trend. I am looking for similar datasets from further afield.

 

I still don't know for sure which way this is gonna go, In one sense IF man is responsible maybe we can reverse it, If not then whatever the cause we'll just have to 'ride it out' we've done it before we can do it again.

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