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Comment by bnolsen | Hacker News Reader

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.

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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 unreasonable.

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...

What's your source on this? As someone who doesn't normally follow these kinds of reports, does NOAA have a history of falsifying data?

Further, what's your source on your last statement, that global temperatures are dropping?

I suspect it is from Tony Heller (aka Stephen Goddard). Looks like he has a blog post about it here [1]. (note: Heller is nuts so it is hard to take what he says at face value, but it would appear he has a valid point on all the temperature adjustments going on).

The NOAA does adjust the data (and continues to do so) based on various factors like time of observation (TOBS), urban heat island effect (UHI). As well as infilling data when a station drops or they don't have the coverage.

As for the global temp dropping. That is most likely based on the satellite data showing a slight decrease (the hiatus).

[1] https://stevengoddard.wordpress.com/2015/08/17/the-majority-...

Rather than trying to fill in data that we don't have, are there models based on only the data that we actually have?

Why do you believe this? One making an accusation of that nature should cite sources.

If you don't trust the NOAA, just check the Russian, Chinese, or European climate models and temperature measurements.

I guarantee you they'd be happy to prove America wrong on the world stage, so there's an incentive for them to be accurate.

do you have any reference?

Climate change deniers are required to provide proof.

More than half? Is that a made up number?

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