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Comment by CivBase | Hacker News Reader

> So what climate scientists have been doing for decades?

https://en.wikipedia.org/wiki/Arctic_sea_ice_decline#Ice-fre...

> Many scientists have attempted to estimate when the Arctic will be "ice-free". Professor Peter Wadhams of the University of Cambridge is among these scientists; Wadhams in 2014 predicted that by 2020 "summer sea ice to disappear," Wadhams and several others have noted that climate model predictions have been overly conservative regarding sea ice decline. A 2013 paper suggested that models commonly underestimate the solar radiation absorption characteristics of wildfire soot. In 2007, Professor Wieslaw Maslowski from the Naval Postgraduate School, California, predicted removal of summer ice by 2013; subsequently, in 2013, Maslowski predicted 2016 ±3 years.

Looks to me like there have been plenty of overly-alarming predictions about a Blue Ocean Event over the last two decades.

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Are you serious right now? Do you realize how hard it is to predict this stuff?

You actually expect them to nail it down to the year? lol

Well, if someone is predicting an event 3 years into the future, then... yeah!

What makes you think I expect them to make an accurate prediction down to the year?

The last prediction from that quote was made in 2013 and predicted 2016 +/- 3 years.

Inaccuracies aren't the issue here. The problem is that well-intentioned scientists and politicians are making overly-alarming predictions that keep eroding the populations trust when they keep failing to come true. How do you convince someone to believe you when you say climate change is a real, serious, and immediate threat when they have been lied to about the subject over and over again?

The context of that prediction were the extreme records set by sea ice in 2012, when it did almost disappear. That made some scientists think that we were seeing a nonlinear phase shift and that it would not recover. It did recover, and resumed its linear downward trajectory.

But if your takeaway from that is that scientists are overconfident and wrong, that is insane, because the important thing to know about sea ice is that at its yearly minimum, its volume is a third of what it was in 1980. No matter how you cut it, it's almost gone.

https://twitter.com/ZLabe/status/1314620374601003008?s=19

> But if your takeaway from that is that scientists are overconfident and wrong

my takeaway is that every years hundred models are given birth, every year later the model fitting the data best survive, and two year later when that last model prediction fail, a new model from the previous that that predicted the change better replaces it, in a never ending cycle of bullshit.

the models go both way: without a predictive model that can hold water, how do you know which parameter to tune to resolve the climate crisis?

You’re describing how models improve over time with additional data and better knowledge about the atmosphere.

Or models over fitted to past data with 0 predictive capability that need to be re-tuned every year or two.

He did not say the scientists are overconfident and wrong.

He said they hurt the public trust in climate science when their predictions do not reliably come true.

What hurts public trust in climate science is primarily a massive and well funded propaganda campaign that's been going on for 50 years.

Some scientists are going to sometimes be wrong about things. It is impossible for them to be scientists otherwise.

Neither of us denied any of that.

OP just said that conservative predictions are better than aggressive ones, as they're more likely to come true and thus build trust.

Do you see any evidence that the consistent under-shooting of IPCC consensus predictions has built trust?

It is not possible to have an accurate mean prediction, and also to have no predictions above the mean.

I never said they did, or that they should focus on trustbuilding instead of aiming for accuracy.

I just pointed out that you were arguing with something other than what OP said.

I would expect them to be aware of and communicate their uncertainty.

from 1970 to 2050±20? no. from 2013 to 2016±3? I absolutely expect it to be within the given error range

That's not overly-alarmy; it's a demonstration of the astounding capabilities of climate models to describe incomprehensibly complex phenomena to a remarkable degree.

Given the references in the comment you are replying to, I think more people might interpret as a demonstration of the astounding degree that climate models can totally miss the mark. And calls into question the degree to which we should base policy decisions - with major negative consequences - on those models.

The wikipedia 'graph talks about one scientist who made an over-aggressive estimate... And then lays out the more 'conservative' estimates, placing the BOE sometime between 2022 and the 2030's or 2040's. That sounds like the process working, to me; there's a range of estimates, and it's foolish to disregard honestly-obtained outliers just because they are on the outside.

As it is, I don't think even the over-aggressive calls have "totally missed the mark"; what we're seeing now says maybe they were off by a few years. In terms of global risk analysis around climate change, that error doesn't really matter all that much. Calling to address a major tipping point a few years early is arguably a feature, even.

I think that's a very forgiving take. I recognize that climate change is extremely complex and it's a huge accomplishment for our models to be as accurate as they are. However, they are clearly not accurate enough to be making statements like "2016 ±3 years". Statements like that are easy ammunition for climate change denial.

It was probably this graph - you can understand how it looked very bad at the time ? http://2.bp.blogspot.com/-Mnr3XCiELco/UFxdVV5QMfI/AAAAAAAAFC...

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