July 2015 was warmest month ever recorded • Hacker News Board

Re: July 2015 was warmest month ever recorded

#51

Post by scarmig » Thu, Aug 20, 2015, 4:48 PM UTC

elektromekatron wrote: post #29

I find it continually amazing how many people find NASA sending rockets into space all the time to be an expected and everyday part of modern life, but then don't trust them with a thermometer.

Temperature measurement is a hard problem, hard enough you could write a PhD on it. Asking questions about methods etc. is entirely acceptable.

The issue is when people refuse to recognize that thousands of scientists have made this their career, and thousands of PhDs actually have been written on temperatures past and present, and think that talking heads on Fox News reciting memos paid for by fossil fuel companies contain even the semblance of a real critique.

Re: July 2015 was warmest month ever recorded

#52

Post by zajd » Thu, Aug 20, 2015, 4:49 PM UTC

Carrok wrote: post #39

It's interesting to me that if you say "today was hotter than any day on record" The answer given always seems to be global warming. However if you say "today was colder than any day on record" (also happens very frequently) the answer given is "That's weather, not climate." Edit: Apparently this is not interesting to HNers. Bring on the downvotes.

It's not interesting because if you are talking global temperatures (which is what the article is about) we haven't had a coldest month ever recorded in... decades.

Re: July 2015 was warmest month ever recorded

#53

Post by adevine » Thu, Aug 20, 2015, 4:49 PM UTC

Carrok wrote: post #39

It's interesting to me that if you say "today was hotter than any day on record" The answer given always seems to be global warming. However if you say "today was colder than any day on record" (also happens very frequently) the answer given is "That's weather, not climate." Edit: Apparently this is not interesting to HNers. Bring on the downvotes.

It's not interesting to HNers because it has nothing to do with what the article says. The article is talking about the average temperature across the entire surface of the Earth, for the entire month of July. You are talking about when one very small bit of geography has a local minimum or maximum temp.

Re: July 2015 was warmest month ever recorded

#54

Post by xefer » Thu, Aug 20, 2015, 4:49 PM UTC

atourgates wrote: post #27

Is it possible to separate the warming that's caused by man-made pollution/CO2 from the earth's natural cycles? Obviously, we're getting warmer because of pollution, but is that on-top of a natural warming cycle? Being partially counteracted by a natural cooling cycle? Could we all be saved by an ice-age?

It may be just the opposite; i.e, the Earth is actuallly in a cooling cycle so the current warming is even worse than indicated.

There was an article in Scientific American back 2005 where the author claims that human activity since the dawn of agriculture may have held off a return to an ice age:

https://physics.ucf.edu/~britt/Climate/Reading5-Did%20humans...

This very much does not mean that the current warming is in any way a good thing.

Re: July 2015 was warmest month ever recorded

#55

Post by rdtsc » Thu, Aug 20, 2015, 4:50 PM UTC

rnovak wrote: post #41

cryptoz wrote: post #26

Earlier quoted context omitted.

There are significant temperature records that go back much farther than 1880 even. Many navies and armies kept records from all over the world, so we actually have lots more data than people think. There are also bodies of science that deal with 'aftcasting', which is making a weather forecast for a date in the past. These techniques have been refined to the point where we can make 1-day aftcasts for ~1850 that are…

To be honest, and this is my opinion only, but 2-3 day forcasts, at least in my area, are horribly inaccurate . In my state, it's a common joke that being a meteorologist is the only job you can have where you can be wrong 95% of the time, and still keep your job. Seriously, our forecasts are nearly always wrong. So.....saying we can make as accurate of forecasts for 200 years ago...that's not really saying much. Thi…

> So.....saying we can make as accurate of forecasts for 200 years ago...that's not really saying much.

It is saying quite a lot actually because the past has already happened. In the first case you are talking about the future, and yes, in some places weather is more unpredictable. You can of course move to the desert and enjoy clockwork predictable weather if it bothers you that much.

The OP was talking about "afcasting" though. In that case measurement have already been taken, but there are other records: ice cores, sea sediment, and many others. So it makes for a very interesting topic.

Re: July 2015 was warmest month ever recorded

#56

Post by pdkl95 » Thu, Aug 20, 2015, 4:50 PM UTC

Afforess wrote: post #7

bnolsen wrote: post #2

sure. more than half the data used in their models is fake made up numbers. Can't trust anything noaa has to say. using non made up temperature data shows we're actually very slightly cooling.

I don't see why using inferred/model data is a bad thing. It is simply not feasible to measure the temperature at every location in the world. Satellite data, combined with in-situ and model calculations can very accurately fill in for missing data. The only other option here is to sit on our hands and say "oh well, I guess we can't predict the weather because we don't have perfect data", which is completely unreason…

There is another potential concern besides the inferred data (which, as you say, should be reasonable), though I don't know how much it would affect any of the larger conclusions (if they are affected at all).

[also, this reference is somewhat old now; I haven't checked if this problem has been addressed in more recent models]

There is evidence[1] that the climate model software doesn't handle floating point properly (which is, unfortunately, a very common problem).

    "... there exist differences in the results for different ... parallel
    libraries, and optimization levels, primarily a result of the treatment
    of rounding errors ... the ensemble spread due to the differences in
    software system is comparable to the ensemble spread due to the
    differences in initial conditions ..."

Rounding errors on different hardware, operation ordering, and optimization level screams that the software isn't properly handling[2] IEEE 754 floating point. This could be a serious problem in an iterated model that is chaotically sensitive to initial conditions (hence the use of ensemble forecasting).

/* regardless, we need a lot thorium reactors ASAP */

[1] http://journals.ametsoc.org/doi/abs/10.1175/MWR-D-12-00352.1

[2] (pdf) https://ece.uwaterloo.ca/~dwharder/NumericalAnalysis/02Numer...

Re: July 2015 was warmest month ever recorded

#57

Post by magicalist » Thu, Aug 20, 2015, 4:51 PM UTC

soneca wrote: post #35

wsterling wrote: post #12

Earlier quoted context omitted.

Your comment just seems redundant. The title says "ever recorded" right in it. It does not simply say "Hottest Month Ever".

Not redundant at all. 'Recorded' could mean since 1930 or 1600. It was a useful comment for me

Well "recorded" already narrows it down to the history of thermometers (largely 17th century and later), then the very first bullet point in the article mentions that the dataset is 1880–2015, which really clears that matter up, I'd say.

So, "useful" in the sense of "let me summarize the article in two words so you can reach your own conclusions instead of clicking that link and reading NOAA's".

Semi apologies for the snark, but yes, the first comment really was an almost informationless attempt to derail. Success!

Re: July 2015 was warmest month ever recorded

#58

Post by wmeredith » Thu, Aug 20, 2015, 4:51 PM UTC

elektromekatron wrote: post #29

I find it continually amazing how many people find NASA sending rockets into space all the time to be an expected and everyday part of modern life, but then don't trust them with a thermometer.

The American GOP and their fossil fuel powered deep pocket backers have done a wonderful job making this an emotionally, and even religiously charged issue (as all good wedge issues should be).

More reading: http://www.washingtonpost.com/news/energy-environment/wp/201...

Re: July 2015 was warmest month ever recorded

#59

Post by Zikes » Thu, Aug 20, 2015, 4:52 PM UTC

That's what they said last month! Get your story straight, scientists!

Re: July 2015 was warmest month ever recorded

#60

Post by antimagic » Thu, Aug 20, 2015, 4:52 PM UTC

Carrok wrote: post #39

It's interesting to me that if you say "today was hotter than any day on record" The answer given always seems to be global warming. However if you say "today was colder than any day on record" (also happens very frequently) the answer given is "That's weather, not climate." Edit: Apparently this is not interesting to HNers. Bring on the downvotes.

Firstly, this wasn't about one day, it was about one month. That already removes a lot of variability out of the data, particularly when you're talking about "global" temperature.

Secondly, "hottest months on record" are happening far more frequently than coldest months ever. Like orders of magnitude more frequently. So yeah, it's not that we're not interested, it's that you re factually wrong.