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acer401
2004-Jan-16, 03:01 AM
Here we are in our 3rd day in a row of almost record breaking low temperatures...Who ever started this global warming nonsence, has not lived in this part of the world in January...

Swift
2004-Jan-16, 03:30 AM
I suspect you are making a joke, so I'm being foolish to give a serious answer. But that rarely stops me.

Don't confuse climate (global warming, large scale, long term) and weather (local, day to day). Plus, there are models of global warming that predict an overall temperature increase, but parts of the world getting colder (because of changes in wind streams and ocean currents).

Normandy6644
2004-Jan-16, 03:44 AM
This reminds me of a Drew Carey comedy special when he was talking about how cold Cleveland was.


"Where's all this global warming we've been hearing about?...all I do is sit outside with an aerosol can and spray....

:lol:

Karthesios
2004-Jan-16, 04:12 AM
It is a bit fun to think about, especially considering I just read an article saying how it recently got warmer at the Mars Rover landing site than in many places in the northeast.

Taks
2004-Jan-16, 06:00 AM
isn't this a topic for another forum? particularly given the, ahem, political nature of it's very premise. :)

but, in the interest of education, what swift said is true. any "global" trend in the weather won't show up as heat waves or extended cold periods, either. even the last ice age was only a few degrees cooler on average around the globe and all of the US was covered in ice! (well, most of it).

a good example... it may be colder than normal where you live, but here in colorado springs, it's been in the 50s every day for a week and even hit 60 just the other day. unseasonably warm, yes, but no records are being broken (yet) and this kind of thing happens occasionally. of course, it's down to 20 every night and the highs for next week are pegged in the low 20s so all is back to the "perceived" norm. :)

mark

Musashi
2004-Jan-16, 07:12 AM
Colder? We've had 80s all week! \:D/

dgruss23
2004-Jan-16, 01:00 PM
isn't this a topic for another forum? particularly given the, ahem, political nature of it's very premise. :)


But it is possible to talk about the science of this issue if those involved in the debate can set aside the politics. :)

Here (http://www.badastronomy.com/phpBB/viewtopic.php?t=10177&start=0) was a recent thread that discussed this and politics came in a little, but it was focused on the science.

Kaptain K
2004-Jan-16, 01:09 PM
Don't confuse climate (global warming, large scale, long term) and weather (local, day to day).
As my brother likes to say, "climate is what we expect, weather is what we get".

Argos
2004-Jan-16, 04:08 PM
Who ever started this global warming nonsence, has not lived in this part of the world in January...

Well, maybe you should try 23 degrees south this January. You would see what they mean by global warming...

The Shade
2004-Jan-16, 04:47 PM
Colder? We've had 80s all week! \:D/

:P I'm thinking some really bad thoughts, but since this is a family oriented website, I'll refrain from writing them.

We've also been having ultra cold temparatures all week. Minus 20 degrees celcius (I'm Canadian) with wind chills of minus 40. Brrr! The worst part is that Alberta has been having Chinook winds all week, and have been enjoying record high temperatures. :evil:

Spacewriter
2004-Jan-16, 04:48 PM
Sure -- if we were on Mars these would be balmy days indeed!

:lol:

Dancar
2004-Jan-16, 06:58 PM
isn't this a topic for another forum? particularly given the, ahem, political nature of it's very premise. :)


But it is possible to talk about the science of this issue if those involved in the debate can set aside the politics. :)

Here (http://www.badastronomy.com/phpBB/viewtopic.php?t=10177&start=0) was a recent thread that discussed this and politics came in a little, but it was focused on the science.

And when political decisions are based on Bad Science, including possible Bad Astronomy in the case of assuming the Sun's thermal radiance to be a constant when discussing causes of global warming, then it becomes a topic that should be discussed here.

Dancar

sts60
2004-Jan-16, 07:21 PM
Solar variance should be included to the extent it adds energy impinging on the Earth. But a higher incident flux doesn't necessarily raise temperatures in any sort of linear manner... In any case, given the fact that we have to live in any mess we create, my politics leans towards a certain amount of prudence.

dgruss23
2004-Jan-16, 09:34 PM
And when political decisions are based on Bad Science, including possible Bad Astronomy in the case of assuming the Sun's thermal radiance to be a constant when discussing causes of global warming, then it becomes a topic that should be discussed here.

I certainly agree. Its nice that in a forum like this the science is at least given consideration.

There is a lot still to be understood regarding the solar forcing of climate. For example, there may be more ways than direct effects of changing solar variance in which the solar cycle has input on climate. I was reading something recently that suggested that cosmic rays may play a role in cloud cover (http://xxx.lanl.gov/abs/astro-ph/0209252). Since the Sun's magnetic activity/energy is higher at sunspot maximum, the solar wind is stronger and fewer cosmic enter the Earth's atmosphere. This could lead to an additional effect via greater cloud cover at sunspot minimum.

If this turns out to be the case, then this might address concerns as to whether variations in solar variance are enough to have actually effected the apparent changes in the Earth's climate. The effect of the solar cycle would be a combination of changes in solar output and changes in cloudcover - plus anything else that is uncovered.

kucharek
2004-Jan-16, 09:46 PM
There is a theory that global warming may change the circulation of the Gulf Stream. Then, Europe will become a pretty cold place.


Don't tell Don Rumsfeld...



Harald

Phix
2004-Jan-16, 09:51 PM
During a discussion about how absurd the movie Waterworld is (for many reasons) There was a link to a website that calculated out the amount of ice in the world and then determined that if ALL the ice melted, there would actually be MORE livable land with a temparate climate... Such as Canada, Greenland, Siberia, Antartica...

dgruss23
2004-Jan-16, 10:01 PM
During a discussion about how absurd the movie Waterworld is (for many reasons) There was a link to a website that calculated out the amount of ice in the world and then determined that if ALL the ice melted, there would actually be MORE livable land with a temparate climate... Such as Canada, Greenland, Siberia, Antartica...

:D

But that raises another issue - everybody assumes that warming would result in catastrophe. As we talked about in the other thread, the computer models cannot be counted on yet. The science needs to be given a chance to develop. In the 1970's they were screaming about ice ages. Now this.

DJ
2004-Jan-16, 10:15 PM
funny, i read somewhere recently that global warming has been going on since our switchover from club-bearing cavemen to focused farming. read: thousands of years.

biology produces much more in greenhouse gasses then those aerosol cans ever did. global warming is a byproduct of grazing cattle, and the expansion of the human herd, but probably not CFC's and automobile mufflers.

i also agree that solar variances would have a much larger affect than we are giving credit for. you're right on target, dgruss

man measures something for 100 years and assumes any trend seen (and even that is questionable) MUST be the result of industrialization. [looks over his should for greenpeace activists in their dingy]

nebularain
2004-Jan-16, 11:39 PM
isn't this a topic for another forum? particularly given the, ahem, political nature of it's very premise. :)


But it is possible to talk about the science of this issue if those involved in the debate can set aside the politics. :)

Here (http://www.badastronomy.com/phpBB/viewtopic.php?t=10177&start=0) was a recent thread that discussed this and politics came in a little, but it was focused on the science.

Well, not to make this a political debate, but it is kind-of funny.

I heard on the news this morning that today Al Gore was supposed to be in NY, I think, giving a speach on global warming!

Good timing! #-o

acer401
2004-Jan-17, 12:24 AM
I am still not convinced that there is global warming going on...Maybe if we were breaking record high temperatures all over the world then there could be something to it...However this is not the case from what I have seen, and to say that some parts of the world are getting warmer and some colder is pretty lame evidence...The only force that determines temperature is the position of the jet stream...If it is north of a persons location then it will be warm....South and it will be cold...At least that is what the weather man tells us.... :wink:

dgruss23
2004-Jan-17, 12:28 AM
I heard on the news this morning that today Al Gore was supposed to be in NY, I think, giving a speach on global warming!

Good timing! #-o

Did the people in NY (actually I'm in NY, but not the city) realize they were going to a speech on why global warming is bad, or did they think they were going to a rally in support of global warming?

Hey, has anybody ever done that? Can you imagine the reaction if somebody put on a global warming rally? Wow, I bet that would make the usual riots at a WTO meeting seem like passive dissent.

Tim Thompson
2004-Jan-17, 02:53 AM
I usually avoid global warming as a discussion topic, primarily because so many people have so much political baggage to bring with them, that a reasonable discussion rapidly becomes impossible. But it really is an important topic, so I guess I'll just chime in any way. I have some experience in research along these lines, as I was responsible for assessing atmospheric radiative transfer models & chemical models for the Advanced Spaceborne Thermal Emission and Reflection Radiometer (http://asterweb.jpl.nasa.gov/). But we were interested in surface imaging, and not the atmosphere, except that it's in our way.

As I see it, there are two questions:
1) Is the earth actually warming up?
2) If so, to what extent, if any, are people responsible for it?

As to question 1, there is absolutely no doubt at all but that the earth is warming dramatically. There is no excuse for any scientist to say otherwise in the face of more than overwhelming data. See, for instance, the Surface Temperature Analysis (http://www.giss.nasa.gov/data/update/gistemp/), and the Global Temperature Trends (http://www.giss.nasa.gov/research/observe/surftemp/) from the Goddard Institute for Space Studies (http://www.giss.nasa.gov/). But that's only one of many sources that will tell pretty much the same story, like the Global temperatures (http://www.met-office.gov.uk/research/hadleycentre/obsdata/globaltemperature.html) analysis at the UK Meteorological Office (http://www.met-office.gov.uk/). the warming of the earth is an undeniable fact.

However, the answer to question 2 is not so easy. There are certainly good reasons to believe that human activity has something to do with global warming. We know that the abundance of CO2 in Earth's atmosphere has gone up sharply over the last century or so, primarily due to industrial activity. We also know that this will increase the effective heat capacity of the atmosphere, which means higher temperatures and more thermal energy stored in the atmosphere. But we don't know how much temperature change, or energy storage to expect from a given abundance of CO2, since there are model dependencies to mull over.

On the other, we know that there are considerable excursions in global temperature from the geological record, in the long pre-industrial, pre-human past. We also know that the sun is variable on the ~1% level, and that Earth's weather/climate system will respond to that variability. And we know that the climate system is "chaotic", in that it can make large changes over short periods of time, even when presented with small changes in input. But we don't know how much change to expect from a given natural variance. And we still don't know the whole story of the land-water-air interactions. The oceans store a lot more heat energy than the atmosphere, and it is very likely that climate will respond rapidly (on the order of 10 years) to significant changes in ocean current circulation (topex-Poseidon examones the North Atlantic current (http://www.gsfc.nasa.gov/topstory/20010716gulfstream.html)).

Nobody knows whether or not "we" are screwing up our own climate. But we do know that we could be, and if we wait until we really know, before doing anything about it, we may well have waited too long.

Chip
2004-Jan-17, 03:07 AM
Tim Thompson -
Thank you for some very informed answers and ideas. Are there any studies or models that suggest that global warming would cause an inverse side-effect of increasingly severe winters? Just curious.

acer401
2004-Jan-17, 03:37 AM
Nice post Tim and very thorough...My question however is the same....Other than a bunch of graphs that show a upward trend in surface temperature, there is not much else to go on that the earth is getting warmer...I still feel that if the temperature is getting hotter by the second, we should be setting new records somewhere around the world almost daily...Also I feel that setting record lows, like we have this week should be a thing of the past but obviously not...I am still not sure how that fits in with global warming...

ZaphodBeeblebrox
2004-Jan-17, 12:36 PM
Actually, it's rather simple.

The Increasing Average Temperatures, are driving up the Strength of The Weather Fronts.

This would tend to move Even The Jet Stream, around more violently, creating a Greater Temperature Differential by Latitude, thus Increasing the Wind Speed further.

Now, what happens when the Weather gets So Intense, that The American North-East, gets hit with a Massive Wind Gust, moving South from Canada?

dgruss23
2004-Jan-17, 04:13 PM
Tim Thompson: Nobody knows whether or not "we" are screwing up our own climate. But we do know that we could be, and if we wait until we really know, before doing anything about it, we may well have waited too long.

My concern is that we don't know

1. If we need to do anything and
2. If what is being proposed would actually make a difference if there is an impending problem.

But if you look at the graph at this link (http://www.giss.nasa.gov/research/observe/surftemp/) which you provided you can clearly see the downward temperature trend between 1940 and 1975. That is the trend that caused all the impending ice age panic in the 1970's.

Why did we have a 35 year cooling trend even as CO2 was being increased? Perhaps you reach a point where the effects of CO2 kick in and we just haven't seen that yet. But the overall increasing trend during the last century is part of a larger trend going back to the little ice age and Maunder minimum.

And isn't there still uncertainty in the paleoclimate record as to whether CO2 increases precede warming trends or result from warming trends? For example, in 1999 there was an article in Nature (vol 399, pg 313) that found evidence that CO2 changes did not necessarily track with temperature changes during the miocene.

For those that are interested I linked to some articles that discuss the Sun's role in climate here. (http://www.badastronomy.com/phpBB/viewtopic.php?p=74158#74158)

Certainly there is more to be studied, but it seems in the global warming debate there is a lot more being proposed (Kyoto and so on) than solid science that justifies the need for those proposals or even that the proposals would make a positive difference.

aurora
2004-Jan-17, 11:11 PM
Nice post Tim and very thorough...My question however is the same....Other than a bunch of graphs that show a upward trend in surface temperature, there is not much else to go on that the earth is getting warmer...

Are you aware of what has happened and is happening to glaciers all over the world?

DJ
2004-Jan-17, 11:48 PM
i read somewhere once, might have been right after Mount St. Helen eruption, that the amount of gases spewed into the atmosphere through one major volcanic eruption far surpasses anything that humans have done throughout all of time.

aurora
2004-Jan-19, 06:15 AM
i read somewhere once, might have been right after Mount St. Helen eruption, that the amount of gases spewed into the atmosphere through one major volcanic eruption far surpasses anything that humans have done throughout all of time.

That is incorrect. At least, I know that the annual amount of CO2 spewed by volcanoes is far less than that produced by humans.

If you do a search, you can find some university or government web pages that give various tonnages or percentages.

aurora
2004-Jan-19, 06:19 AM
Science Friday recently (Jan 9) had a segment on climate change and biodiversity.

http://www.sciencefriday.com/pages/2004/Jan/hour1_010904.html

Current issue of Discover (yah, I know, it's not a rigorous journal, but sometimes they get stories from reputable sources) has an article about melting arctic ice.

Diamond
2004-Jan-21, 01:12 PM
i read somewhere once, might have been right after Mount St. Helen eruption, that the amount of gases spewed into the atmosphere through one major volcanic eruption far surpasses anything that humans have done throughout all of time.

That is incorrect. At least, I know that the annual amount of CO2 spewed by volcanoes is far less than that produced by humans.

Link? Proof?

aurora
2004-Jan-21, 07:23 PM
Link? Proof?

Well, like I said, a search will turn it up. For example, I asked Jeeves, and got this, from
http://www.umich.edu/~gs265/society/volcanoes.htm


Carbon dioxide is one of the main causes of the Greenhouse effect, but there are not significant amounts for the carbon dioxide emitted from volcanic eruptions to contribute to the Greenhouse effect. Humanity is responsible for emitting 110 billion tons of carbon dioxide each year, while volcanoes only contribute 10 billion tons (Fisher).

Similarly, from http://vulcan.wr.usgs.gov/News/Announcements/summer_2001_seminars.html


Volcanoes and Greenhouse Gases: Do Volcanoes Put Out as Much Carbon Dioxide as We Do?
Terry Gerlach, US Geological Survey, Cascades Volcano Observatory

The greenhouse gas carbon dioxide (CO2) is the most abundant gas (after water) emitted by volcanoes. Volcanologists estimate an annual global output of 200 million tons of volcanic CO2 per year. This natural source is balanced by natural processes that remove CO2 from the atmosphere-specifically by the weathering of rock into soil by atmospheric CO2 dissolved in rain and surface waters. By comparison, human activities such as the burning of fossil fuels and deforestation produce 130 times more CO2 than all the world's volcanoes put together (adding 26,000 million tons of CO2 to the atmosphere each year, the equivalent of 8,000 Kilaueas (Hawaii's most active volcano). This comparison suggests humans are producing CO2 at a rate unprecedented in a geological history stretching back many millions of years. Clearly, there is need to think seriously about the implications of human CO2 emissions and to consider how current energy policy and land use practices may impact our collective future.

Whether volcanoes spew out 200 million tons or 10 billion tons of CO2 each year, it is peanuts compared to our industrial output. And anyway, volanic activity has not globally changed since the start of the industrial revolution.

BTW, this was discussed awhile back in, of all places, the Planet X forum here. So a search on this website might turn that up.

More, from http://www.climatenetwork.org/canglossary.html


Carbon Dioxide (CO2). The greenhouse gas whose concentration is being most affected directly by human activities. CO2 also serves as the reference to compare all other greenhouse gases (see carbon dioxide equivalents). The major source of CO2 emissions is fossil fuel combustion. CO2 emissions are also a product of forest clearing, biomass burning, and non-energy production processes such as cement production. Atmospheric concentrations of CO2 have been increasing at a rate of about 0.5% per year and are now about 30% above preindustrial levels. (EPA)