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rhaig 0
Quote
You selectively quoted of just one side of his position. I provided balance. Stop being so defensive.
and you are ASS-uming that was my intention when I really just wan't trying to spam the thread with crap that people could go read on their own. But you leapt to a different conclusion and now we have spammed the thread with bunch of useless crap instead. Maybe next time I'll just quote the entire article plus any comments so you don't have to click on anything. But then you'll hammer me for over-quoting.
wait... you're a professor... it's not right unless it's done your way. (regardless of whether it's actually right or not)
My bad.
Rob
QuoteOne of the primary reasons that that spread is so wide is that we have no idea what people will do.
Correct. But "there's a very remote chance that the sea level will rise 3 feet in the next hundred years" doesn't generate the headlines. The quotes from the scientists aren't about "our minimum predicted is more consistent with observed trends for the last 100 years." They are dire.
QuoteWill people ignore everything about climate science, the risks of pollution and burn as much coal and oil as they can?
That's what they've been doing. So let's look at the trend. Ah! I see the trend! The last hundred years! The last 30 years! So we've got evidence of the sea level changes when people are burning fossil fuels left and right. That data was ignored.
QuoteWill we start taking the threat very seriously, and drastically curtail our emissions of CO2? Expect the bottom of that range.
We haven't been taking the threat seriously. We've been below the bow the bottom of that range. That's my problem.
It's like predicting a 600% increase in the lung cancer deaths if smoking continues to grow like it is. People would say, "We've got a century of evidence. Why aren't you looking at historical death rates when predicting future death rates?"
QuoteSo if you tell scientists what way our society will go, they can give you a better prediction.
I'm beginning to question this, as well. Sea level is pretty flat the past 30 years - which is when acceleration should have started. Under the theory, we should be increasing the ice pack in Greenland and Antarctica. But we're not hearing about anything other than "it's melting."
So I'm becoming increasingly bothered by the predictions because they are all over the place. Predictions are we'll see hotter/colder, wetter/drier, snowier/not snowier, more hurricanes/fewer hurricanes, etc.
Such predictions don't breed confidence.
My wife is hotter than your wife.
billvon 3,078
>>as much coal and oil as they can?
>That's what they've been doing.
OK, I assume you mean that one can thus predict that will happen in the future as well. If we assume they will continue doing this, then we are at the worst case assessments. Thus there is good reason for scientists to predict the far end of the curve.
>It's like predicting a 600% increase in the lung cancer deaths if smoking continues
>to grow like it is. People would say, "We've got a century of evidence. Why aren't you
>looking at historical death rates when predicting future death rates?"
And they would. If we saw a 100% increase in lung cancer based on going from a 1% to 2% population of smokers, then increasing that population to 7% would indeed entail an increase of 600% if the relationship was linear.
>So I'm becoming increasingly bothered by the predictions because they are all over
>the place. Predictions are we'll see hotter/colder, wetter/drier, snowier/not snowier,
>more hurricanes/fewer hurricanes, etc. Such predictions don't breed confidence.
No, they don't. But if you get your predictions from the popular media, you won't get many accurate predictions anyway.
Quote
>So I'm becoming increasingly bothered by the predictions because they are all over
>the place. Predictions are we'll see hotter/colder, wetter/drier, snowier/not snowier,
>more hurricanes/fewer hurricanes, etc. Such predictions don't breed confidence.
No, they don't. But if you get your predictions from the popular media, you won't get many accurate predictions anyway.
It wasn't the popular media that created these predictions. The hurricane one is especially noted as we continue a very long period without a severe hurricane on land, but years back when the east got hammered, the claims were flying like mad.
QuoteIf we assume they will continue doing this, then we are at the worst case assessments.
And my point is that we are seeing worst case assessments.
Here's what I find to be reasonable:
"Hey, what happens if people keep pumping more and more CO2 into the atmosphere?"
"Let's take a look at the last 100 years."
"Oh, yeah."
"Then we factor in what increases will do."
"Good idea."
Here's what's happening.
"Hey, what happens if people keep pumping more and more CO2 into the atmosphere?"
"Sea level will rise 3 feet by the end of the century."
"How do you know what?"
"We know these things."
"Well, why not look at the last 100 years and see what it's done."
"No."
"But it shows a pretty marginal increase in sea level. About 6 inches per hundred years, and it's been stable for the last 30 or so years.'
"Well, my model says sea levels will rise between 18 inches and 54 inches."
"54 inches? WOW!"
"Yep. That's the figure the press will grab hold of."
"Then we factor in what increases will do."
"Good idea."
My wife is hotter than your wife.
billvon 3,078
Here are the NOAA predictions from 2008:
================
It is premature to conclude that human activities--and particularly greenhouse gas emissions that cause global warming--have already had a detectable impact on Atlantic hurricane activity. That said, human activities may have already caused changes that are not yet detectable due to the small magnitude of the changes or observational limitations, or are not yet properly modeled (e.g., aerosol effects).
Anthropogenic warming by the end of the 21st century will likely cause hurricanes globally to be more intense on average (by 2 to 11% according to model projections for an IPCC A1B scenario). This change would imply an even larger percentage increase in the destructive potential per storm, assuming no reduction in storm size.
There are better than even odds that anthropogenic warming over the next century will lead to an increase in the numbers of very intense hurricanes in some basins—an increase that would be substantially larger in percentage terms than the 2-11% increase in the average storm intensity. This increase in intense storm numbers is projected despite a likely decrease (or little change) in the global numbers of all tropical storms.
Anthropogenic warming by the end of the 21st century will likely cause hurricanes to have substantially higher rainfall rates than present-day hurricanes, with a model-projected increase of about 20% for rainfall rates averaged within about 100 km of the storm center.
==================
Now, "there are better than even odds that very intense hurricanes will increase in some basins" "it's too soon to say if AGW is having an impact, but it may" and "2-11% increase in intensity" does not sell papers. "KILLER HURRICANES!" does.
billvon 3,078
In this case, you just set the conditions that result in worst case assessments (i.e. worst case emissions profiles.) If you don't like them, then set different conditions. You can't say "my initial conditions are just guesses, but it's your fault that the results that are based on them aren't accurate."
============
"Hey, what happens if people keep pumping more and more CO2 into the atmosphere?"
"Let's take a look at the last 100 years."
"Oh, yeah."
"Then we factor in what increases will do."
"Good idea."
============
The above is valid if we stop emitting CO2 right now. The earth will continue to warm until it reaches a new equilibrium, since that CO2 will stay in the atmosphere for decades.
If we increase CO2 concentrations it will warm at a faster rate. If we increase it at a faster rate it will warm at a faster rate still. That's what your stated assumptions above (that we won't care how much CO2 we emit) implies.
Again, if you would prefer a different assumption, great. But you better be very careful about what assumptions you make, especially if you will be incensed by people who give you worst cases based on those assumptions.
Quote>but years back when the east got hammered, the claims were flying like mad.
Here are the NOAA predictions from 2008:
there's more people out there besides the NOAA and the media.
>1.5 inches in 18 years? Okay - that's right at 6 inches per century. 1 foot in 18 years?
>That's an 800% increase in the trend. Tout that! It sounds like something must be
>done.
?? Surely you would not want a scientist telling you only the minimum prediction as if it were fact?
One of the primary reasons that that spread is so wide is that we have no idea what people will do. Will people ignore everything about climate science, the risks of pollution and burn as much coal and oil as they can? You're looking at the high side of that number. Will they make a modest effort to reduce CO2 emissions, and continue development of things like EV's, solar and wind, and next generation reactors? Expect the middle of that range. Will we start taking the threat very seriously, and drastically curtail our emissions of CO2? Expect the bottom of that range.
So if you tell scientists what way our society will go, they can give you a better prediction. However predicting what society will do has always been problematic.
>I'm scratching my head at the methodology. I'm wondering how they can make such
>a prediction with a margin of error between 16 and 54 inches, but focus on the high.
That's pretty common in both science and engineering. If you are in the Army Corps of Engineers, and hear that a storm surge can be between 5 and 15 feet above high tide, how high are you going to design that levee to be?
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