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Comment: "The xxxx in yyyy years" (Score 4, Insightful) 55

by Troed (#49583789) Attached to: Ancient Megadrought Entombed Dodos In Poisonous Fecal Cocktail

Humans remember about thirty years back. Anything that's different today from thirty years ago we feel to be "unnatural". Most processes on earth work over much longer time scales than that - while still being completely natural.

The holocene, our current interglacial, is ~12000 years old. During that time the climate has both been a lot warmer (the Holocene optimum) as well as a lot colder (the Little Ice Age) than now. What we don't really know is how the climate has changed regionally during these thousands of years. We have some insight (the Sahara desert was a lush savannah around 8000 years ago) and there's a lot of research into how the rise and fall of civilizations might be correlated with natural regional climate changes much more than the popular image portrayed by, for example, Jared Diamond.

We do have written records from the last 2000 years (se the linked PDF). It's fascinating read into how heat waves, droughts, extremely cold winters and hot summers etc have affected our forefathers in a way I think we have problems grasping today. If anything, it seems the climate has been unnaturally stable over the last century - even including the famous dustbowl in the US.


Comment: Re:Voting booth (Score 1) 106

by Troed (#49476629) Attached to: In New Zealand, a Legal Battle Looms Over Streaming TV

Yeah, it does make a difference in people who see where this is heading (and fast) actually do their job as voters. The two Swedish politicians who were voted into the European Parliament under the Pirate Party flag made an enormous difference while they were there, and the German Pirate Party MEP who succeeded them has continued to do so being the rapporteur for the parliament's review of the Copyright Directive - something that's happening right now.

Add to that the Icelandic Pirate Party who are making a difference in their national parliament, and are currently polling as the largest party in nation.

The Pirate Party movement is represented in over 70 countries all over the world. The "only" thing that needs to happen to counteract the stupidity of Big Media and Authoritarian Government is for people to do their jobs while at the voting booths.

Comment: Re:If It Ain't Broke, Don't Fix It! (Score 1) 209

by Troed (#49468945) Attached to: Linux Getting Extensive x86 Assembly Code Refresh

"unless a mistake"
"should be preserved"

= best practice is to know and understand that the old bugs will resurface. I.e, there's a cost to do the rewrite (no matter if you call it refactoring or not) that will affect the business for some time after deployment.

Your Software Engineering education seems to be a bit lacking.

Comment: Re:If It Ain't Broke, Don't Fix It! (Score 3, Insightful) 209

by Troed (#49468753) Attached to: Linux Getting Extensive x86 Assembly Code Refresh

I am "in Software" since ~25 years. I also hold a degree as a Software Engineer.

People who obsess about rewriting old code just because it's old tend to forget that in that old code are many bug fixes for edge cases found over the years. It was well documented and part of my education to know and understand that rewriting often caused those same bugs to surface again.

Best practice is to run both the old and new software in tandem for a while and verify the results. In reality no organization besides NASA will do that.

Comment: Re:Strictly speaking... (Score 3, Insightful) 417

I'm less concerned about the number and more concerned about the rate. normally these kinds changes take several magnitudes longer.

We have no idea whether the rate is unusual. There are no proxies with that resolution available.

(But why let science stand in the way of a good scare story?)

Comment: Re:Holy Fuck (Score 1) 304

by Troed (#49444629) Attached to: Obama Says Climate Change Is Harming Americans' Health

I understand the climate models very well. How do you think the input parameters to the models are derived?

The parametrizations also involve numerical parameters that must be specified as input. Some of these parameters can be measured, at least in principle, while others cannot.


The values used for parametrization are based on research that begins with measurements. Those measurements have errors - as in any other branch of science - yet those errors are not propagated through the calculations.

Science thus says that climate models cannot do projections more than a few years out, until the combined error exceeds the projection range.

Comment: Re:Holy Fuck (Score 1) 304

by Troed (#49441429) Attached to: Obama Says Climate Change Is Harming Americans' Health

There's no scientific support - whatsoever - for claiming that there's an expectation of weather to keep within 95% of the "confidence intervals". A model is only as good as its inputs - and measurements (en masse) are what those inputs are created from.

This is well known in all other fields of science, where claims of "confidence intervals" based on model runs would rightly get laughed out of all journals. The error bars of your measurements, inherit in all equipment, must be carried forward in all calculations.

For some reason that's not done in climate science. I don't understand why - there's no difference between "climate equipment" and other forms of equipment.

Comment: Re:Holy Fuck (Score 1) 304

by Troed (#49436643) Attached to: Obama Says Climate Change Is Harming Americans' Health

No, it's actually much much worse. Climate scientists create error bars on their projections by running models with different input parameters. They're not using the actual error variables from measurements and propagating the compounded error forwards in the calculations - which is how it's done in every other branch of science.

If you do that, the projections become meaningless just a few years out. The climate system is absolutely nothing like the single variable coin flip.

I'm very worried about the anti-science stance taken in climate discussions just because it doesn't lead to the preconceived result some hope to show (or even effect).

Comment: Re:wildfires? (Score 1) 304

by Troed (#49436631) Attached to: Obama Says Climate Change Is Harming Americans' Health

California is experiencing the worst drought (ever, perhaps)

Not according to science.

Through studies of tree rings, sediment and other natural evidence, researchers have documented multiple droughts in California that lasted 10 or 20 years in a row during the past 1,000 years -- compared to the mere three-year duration of the current dry spell. The two most severe megadroughts make the Dust Bowl of the 1930s look tame: a 240-year-long drought that started in 850 and, 50 years after the conclusion of that one, another that stretched at least 180 years.

Which of course makes me wonder why so many people feel it's important to claim otherwise.

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