The term has no useful – and certainly no scientific - meaning. Even if it did have a precise definition, Deniers would not understand it and would not care. Just like “statistical significance” – which Deniers talk about all the time even though none of them can tell you what it is – ‘catastrophic’ is a Denier magical incantation to protect them against being infected with scientific knowledge.

Look at Zippi62’s answer. He quotes Wikipedia –

“Temperature anomalies are useful for deriving average surface temperatures because they tend to be highly correlated over large distances (of the order of 1000 km).[10] In other words, anomalies are representative of temperatures over large areas and distances. By comparison, absolute temperatures vary markedly over even short distances.”

– even though he cannot tell you what it means. If he did understand anything – or even if he wanted to pretend that he knew anything - he would have used a definition such as the one provided by NASA:

http://data.giss.nasa.gov/gistemp/FAQ.ht...

In layman’s terms (which he still probably cannot understand), it is analogous to using frequencies (percentages) rather than raw numbers in making comparisons among datasets that may differ in sample depth or in their absolute ranges.

Because of his ignorance, he ends up providing an answer that is so profoundly stupid that it would embarrass any reasonably informed person.

Good question. I don't know why you say you aren't interested in the effects as the effects is what makes warming catastrophic. It may be that 1C is catastrophic, though I doubt it. I would guess somewhere around 10C is catastrophic. Maybe 5C. The evidence for catastrophe is even weaker than the evidence for global warming. This is generally because they assume a high amount of warming when doing the catastrophe argument. There needs to be a little more interaction between the 3 IPCC Working Groups. Indeed, there is a conflict, since to get high amounts of catastrophe, you need high amounts of warming, which requires high amount of CO2. However, the high CO2 doesn't just come out of thin air, it comes from high amount of development, which means that those countries will now not suffer as much catastrophe because they are now wealthier and better able to absorb the effects of the high warming.

To get that high warming, you need to have higher growth rates than the US in the 1800s and 1900s.

That distinction is a product of two things:

1. Intelligent people know that it's completely ridiculous to deny AGW entirely, and would it would make them sound like a simpleton to do so.

2. Denying the "catastrophic" nature of it still gives them an excuse to ignore it.

One "catastrophic" denier says " I don't generally believe in anything without evidence..." which he apparently takes to mean he can ignore several hundred years of science, too--apparently he doesn't believe there is any evidence for things like radiative theory, fluid dynamics or thermodynamics.

Here's a question for Raisin Caine: Would you drive a car into an active lava flow and park it there? I'm pretty sure there is a decided lack of observations of what will happen in such a situation--certainly nothing at any reasonable level of statistical significance. Would you be okay with doing that until such evidence came along?

Maybe if AGW caused more hurricanes:

Hurricanes: http://www.aoml.noaa.gov/hrd/Landsea/gw_...

Guess not.

Tornadoes?: http://www.ustornadoes.com/wp-content/up...

Nope.

Crop destruction?

Corn and wheat yields: http://sustainablog.org/files/2009/08/co...

Nope

Floods/droughts?: http://www1.ncdc.noaa.gov/pub/data/cmb/s...

Nope.

I don't believe in catastrophic AGW, because I don't generally believe in anything without evidence.

What I do believe in, however, is not lying to the general public. When the warmers go around pretending that the world is ending and making claims that all these weather events are caused by AGW, yet have no evidence of this happening only models that are consistently overestimating, that is what I consider lying.

You may have fallen for this BS, simply because you think the ends justify the means, and energy from renewable sources is a good goal. But the ends do not justify the means and the idiotic things being bandied about go from the stupid (like carbon taxes) to the possibly dangerous like geoengineering.

I have no problem with being honest with people and telling them that the temps hav ebeen rising because of man. We are not aware of all of the possible consequences that COULD happen, so it would be safer to limit our CO2 emissions. I have already laid out a plan to do so. It is the greeners who protest, wind, nuclear, geothermal, hydro and every other form of power and have the democrats backed into a wall where the only plan is the idiocy of taxation.

You warmers know the truth. If you really believed the absurd predictions of catastrophic climate change and think we need to act now, then you would not be talking about a stupid tax plan. You have no idea how long it will take your tax plan to reduce CO2, by how much CO2 willl be reduced, nor how much it will cost. I can tell you for certain, it will take more time than my 30 years plan to be nearly CO2 free using nuclear, solar power and e-cars.

Now as for if I believe "catastrophic warming" will occur? I don't claim to know the future. I have seen no evidence that it will occur. BUT, I am naturally inclined to take intelligent precautions. I don't stock up my house for the zombie apocalypse, but I do have some money saved away for a rainy day. You want to discuss intelligent manners of planning for the uncertain future, I am all ears. You want to send everyone into a panic so that they will accept any stupid plan you think of, then you will have me as opposition.

Pegminer, LOL, just more of the same crap. Comparing this to parking a car in lava? When I talk about scare-mongering... This would be one of the assinine analogies I am speaking about. And personally (borrowing from South Park) I don't like your duck-and-cover solution.

I pick 5 degrees C, nine degrees F.

If in 100 or 200 years, no difference. That is catastrophic for the ecologies we are familiar with..

Something not natural.

http://wattsupwiththat.com/2013/10/30/ho...

0.87 degrees in 353 years is natural. It is coming out of a Little Ice Age. Nothing catastrophic there.

Global Warming ended in 2012, confirmed. Mike

I would define "catastrophic" as the weather actually killing people, not just making it more expensive to grow food so that more poor people starve than are starving now.

LOL! Specificity? You ask this when you don't know and can't prove that your own desk isn't a "shape-shifting alien"?

Direct answer : A danger to humans.

There's been 78 major temperature fluctuations in the past 4500 years (1 every 58 years on average) equal to or greater than 0.7C (the current warming in question by climate science), which has taken place over 130 years of instrumental measuring techniques. How good can the science be?

You use the phrase "recent rise in global average temperature" as the basis for your global warming position, yet the "actual" global average temperature is next to impossible to establish in an actual "instrumental temperature record".

" ... Absolute temperatures v. anomalies[edit]

Records of global average surface temperature are usually presented as anomalies rather than as absolute temperatures. A temperature anomaly is measured against a reference value or long-term average.[9] For example, if the reference value is 15 °C, and the measured temperature is 17 °C, then the temperature anomaly is +2 °C (i.e., 17 °C -15 °C).

Temperature anomalies are useful for deriving average surface temperatures because they tend to be highly correlated over large distances (of the order of 1000 km).[10] In other words, anomalies are representative of temperatures over large areas and distances. By comparison, absolute temperatures vary markedly over even short distances.

Absolute temperatures for the Earth's average surface temperature have been derived, with a best estimate of roughly 14 °C (57.2 °F).[11] However, the correct temperature could easily be anywhere between 13.3 and 14.4°C (56 and 58 °F) and uncertainty increases at smaller (non-global) scales. ... " - http://en.wikipedia.org/wiki/Temperature...

Climate science is completely flawed in almost every aspect as long as a global average temperature is being used to establishe the basis for the science. A 30 year trend based on anomalies to establish a temperature base to form the theory of global warming is disingenuous. "Highest temperature ever recorded" means nothing when compared to 4.5 billion years and is a totally misleading statement.

If their was a global average temperature measurement recorded in the 1600s of 54.3F, does that prove it was the coldest global average temperature ever recorded? If it was recorded, then it must be. Does that mean that global average temperatures have risen 3.7F since the 1600s, since it was measured by an instrument?

Alarmism starts by using anomalies to establish "Global Warming". You paint pictures in people's minds that they are causing the warming by using catastrophic weather events caused by temperature fluctuations caused by humans. You prove it with instrumental temperature measurements that mean nothing on a Global scale!!!

An "actual" global average temperature is impossible to establish, yet climate science will continue to show human arrogance about what temperature anomalies mean. The difference between what they do know and consider "facts" and what are "actually" facts is shown in their IP CC reports. Pure climate arrogance!!!

"Catastrophic" is a term used by extremists and they use it to sensationalize an issue.

I wonder where zippi got from. Was it

1. The end terminus of his digestive tract?

2. A denialist blog? or

3. The very scientists that denialists despise, such as James Hansen or Michael Mann?

If his answer is three, I will believe

I've seen several of the saner skeptics and "skeptics" say, in effect, "I believe in AGW, but not catastrophic AGW".

So, skeptics, can you define what you mean by "catastrophic" warming? How bad would warming have to be before you'd agree that we need to take action against it?

And, realists, how bad do you actually expect warming to get? Does it match the skeptics' definitions of catastrophic warming? Or is it merely harmful, but not catastrophic?

Any other thoughts?

200 hundred degrees