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Climate models are running red hot, and scientists don’t know why

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Re: Climate models are running red hot, and scientists don’t know why

#221

Post by jknoepfler »

protanopia wrote: post #119
jknoepfler wrote: post #35

Earlier quoted context omitted.

So if I asked you to bet at 50/50 odds that next year would be colder on average than this year, you'd take the bet?

Are you asking about the weather in one specific year? Weather is not climate.

I'm well aware of the distinction between weather and climate. I was asking if the climate change skeptic would take a bet that the global mean temperature (operationalized in some acceptable way) would decline in 2021 compared to 2020. If they believe that the earth is not, on average, getting hotter, then they should be indifferent to this bet (inter-year variation should be random around a fixed point).

I don't think any intellectually honest person is indifferent to this bet. Everyone believes there is a solid chance that the climate is actually getting warmer, and almost no one would wager serious money at even odds on a globally colder 2021.

If you wouldn't bet against the climate getting warmer, then I don't think you have any place calling yourself a "climate change skeptic"

In a similar vein, I invest in index funds because I'm not a market skeptic. The market (at the moment) tends to grow year over year. I put my money where my mouth is in the market, I'd do the same on global temperature, and I'd win (on average, if I bet year over year, unless something changes dramatically).

Re: Climate models are running red hot, and scientists don’t know why

#222

Post by chrisco255 »

microtonal wrote: post #120
chrisco255 wrote: post #73

A model isn't reality. A lot of climate research is based entirely on experimenting with these climate models. Of course, the climate is a non-linear dynamic system, so even if you had a perfect model (we don't), if your input parameters were off by the slightest bit, reality would veer off wildly from your prediction within a short time. This is why weather forecasts don't work beyond 10 days.

A lot of climate research is based entirely on experimenting with these climate models. We have a lot of data measured at many points on Earth spanning many decades. The data clearly shows that our planet is warming up and that there is a strong correlation with greenhouse gasses. One can extrapolate from these data points with certain reliability. What is hard is to take into account are tipping points (which is why…

We have data that shows warming in the early 20th century, cooling in the mid 20th century (through the 70s) and warming in the decades after that. CO2 ppm was increasing steadily through those ups and downs, so it's not correlated perfectly. Meanwhile there are natural phenomenon like the Atlantic Multi-decadal Oscillation, the Pacific Decadal Oscillation, ENSO, NAO, etc that also correlate quite well with climate change.

In the terms of "bad, unmanageable" climate change, I would invite you to research the early Holocene, which had temps as much as 7 degrees hotter than modern temps. The early Holocene began about 12K years ago and ended about 6K years ago. The warm temperatures correlate with boom times for humanity.

See: Early Holocene Temperature Oscillations Exceed Amplitude of Observed and Projected Warming in Svalbard Lakes

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/201...

Re: Climate models are running red hot, and scientists don’t know why

#223

Post by Reedx »

cagenut wrote: post #150
samatman wrote: post #129

I'm reminded of Feynman's famous anecdote about the Millikan oil drop experiment: Millikan underestimated the charge of the electron, and over the ensuing years, subsequent measurements slowly but surely converged on the correct value. Why? Because experimenters who got the correct value figured it must be too high, and ran the experiment again until they got a more-erroneous value, one that was nonetheless higher. E…

this is textbook middlebrow contrarianism. using some quote from some recognizable name to dismiss the incredible work of dozens of top of their field professionals doing their life's work. its a perfect example of the way hacker news "types" do climate change denial. via endless "well-actuallys" until you're lost and stuck in a level of analysis-paralysis that borders on an anxiety disorder. the problem with solving…

Pointing out that climate models are predictions is not the problem. The models are in fact predictions and they accumulate errors the further out they project. That's just the reality. The problem is pretending otherwise. That muddies the waters and literally fuels and strengthens climate change deniers as it gives them a leg to stand on. Remove that leg. We need to make it harder to dismiss, which can be better accomplished by being clear and factual.

Here is the problem, here is the hard science, here is how we can fix it.

Flat earthers and the like don't get nearly as far in part because they have no such counterpoint to leverage. They remain on the fringes, not taken seriously. Climate change deniers could be relegated to the same fate if we'd be clear about predictions vs science, and ease up on the doomsaying. Doomsayers tend to be ignored for good reason. The world is always said to be ending, yet it never does. Instead it's become drastically better, historically. Global warming is a problem to be solved. Stick to the science.

Re: Climate models are running red hot, and scientists don’t know why

#224

Post by tomaskafka »

chrisco255 wrote: post #73

A model isn't reality. A lot of climate research is based entirely on experimenting with these climate models. Of course, the climate is a non-linear dynamic system, so even if you had a perfect model (we don't), if your input parameters were off by the slightest bit, reality would veer off wildly from your prediction within a short time. This is why weather forecasts don't work beyond 10 days.

> A lot of climate research is based entirely on experimenting with these climate models.

I'd say all of thinking is based entirely on experimenting with mental models. Are you saying your thinking is invalid? :))

Re: Climate models are running red hot, and scientists don’t know why

#225

Post by Angostura »

sp332 wrote: post #183
Angostura wrote: post #92

Earlier quoted context omitted.

I suppose my immediate question is - is there any way for an non-professional with a pair of eyes and a smartphone to contribute in a crowd-sourcy way?

Yeah - get out the vote.

Well, thank you for that helpful suggestion. I was interested in knowing whether the research needed more data points and if so, whether a 'citizen scientist' could contribute.

Re: Climate models are running red hot, and scientists don’t know why

#226

Post by allovernow »

>The scientists went on to try 300 configurations of rain, pollution, and heat flows—something they can do as gods of their own digital earth—before matching the model to history.

Having worked with complex geologic (not climate) models in the past, this is the part that gives me pause. The scientists have set out as a first principle to find warming and then are working backwards and, ostensibly, everything is legitimate because model results are calibrated to previous real data.

But here's the problem. When you have complex, chaotic models with hundreds of freely tweekable parameters, it's fairly easy to fit data and simultaneously get any future prediction you (or your bias) want. Even when individually each variable is within a reasonable range.

We arguably have proof of this happening - climate models have been consistently overpredicting dT for what, 10 years now? There is an institutional problem with climate science, in that there is no real penalty for being wrong, and in fact the more aggressive results probably get the most attention. Because the modeling is so far removed from any sort of experimental or observational data collection, I think the field is dangerously susceptible to institutional bias.

Re: Climate models are running red hot, and scientists don’t know why

#227

Post by mistermann »

wbeckler wrote: post #154
gbasin wrote: post #28

Does anyone know if this is actually true? I was under the impression that climate models have been mostly overshooting reality over the past 40 years > One question modeling can help answer is called “climate sensitivity,” an estimate of how much warmer the planet will be once it has adjusted to atmospheric CO₂ at double the pre-industrial level. (At current rates, CO₂ could reach a doubling point in the last decade…

Here's a systematic comparison of climate model predictions vs reality, since the 1970s. It turns out that the models have done a great job of predicting reality. https://www.carbonbrief.org/analysis-how-well-have-climate-m... I'd be curious where your impression comes from, in terms of what sources of information you're receiving.

Pardon the pedantry, but "-the- models have done a great job of predicting reality" seems like a bit of an overly strong statement. The link you give and the original article seem to be comparing a completely different set of models, and the main article even says there are "dozens still left to report....".

Re: Climate models are running red hot, and scientists don’t know why

#228

Post by lazyjones »

bannable wrote: post #182
lazyjones wrote: post #163

Earlier quoted context omitted.

It is not possible if there aren't valid temperature measurements available for all points throughout the measured period of time, so that many temperatures are "interpolated", estimated etc.

Except that we do have a massive number of recorded temperatures across a massive number of locations in the last 100 years. Climate models, some dating back to the 1970s, have correctly predicted global temperature changes in the 50 years since based on this data. The measurements are real, and there is an established history of the models being generally correct (if not in specific details) by now. Climate study is…

> Climate models, some dating back to the 1970s, have correctly predicted global temperature changes in the 50 years since based on this data.

Can you point me to one such model? One that actually predicted temperatures correctly back in the 1970s and not after various recent "adaptations" like "corrected" emission data?

> The measurements are real

Yes, measurements are real. Interpolations, resulting "global" temperatures and predictions aren't.

Re: Climate models are running red hot, and scientists don’t know why

#229

Post by chrisco255 »

AsusFan wrote: post #98
chrisco255 wrote: post #63

Earlier quoted context omitted.

Could you point me to the academic, empirical research that quantifies the influence of CO2 on climate? Not a book, but from an academic publication.

Assuming that you asking honestly, and not just trying to derail the conversation... Start here: https://skepticalscience.com/empirical-evidence-for-co2-enha... Then proceed to intermediate and advanced. There are a TON of citations for your perusal. After your are done with that, the comments have some additional insights. Have fun. This is quite the rabbit hole to dive into.

Skeptical Science is not an academic publication. It's a blog.

What was the CO2 ppm in the early Holocene? Why was the early Holocene so much warmer than today in spite of lower CO2 concentrations?

Early Holocene Temperature Oscillations Exceed Amplitude of Observed and Projected Warming in Svalbard Lakes

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/201...

Re: Climate models are running red hot, and scientists don’t know why

#230

Post by pjkundert »

tomaskafka wrote: post #220
pjkundert wrote: post #158

> Those now attempting to figure out the mystery of the hot climate models think one factor might have caused the recent unusual results: clouds. It turns out simulated clouds often cause headaches for climate modelers. The impact of cloud cover in these models has been incorrect, and has such a large impact. Doesn't this strike anyone as a major problem? We're burning about 100 billion gallons of aviation fuel per y…

Rough estimate: There are 1.4 × 10^17 liters of water in atmosphere ( https://whyfiles.org/2010/how-much-water-is-in-the-atmospher... ). Your number "about a half a billion metric tons" is 0.5 × 10^12 liters of water, which is 5 orders of magnitude lower number. Or, less than 1/10 000 of atmospheric water. To say in your words, "If I was quoting this number as a significant contribution, I would be embarassed."

The atmosphere at FL300 is super cold and dry. Injecting water there has an enormous impact -- much greater than at lower altitudes, where the bulk of atmospheric water resides.
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