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July 2015 was warmest month ever recorded

ncdc.noaa.gov

21–30 of 211 posts

Re: July 2015 was warmest month ever recorded

#22
post #3

Since 1880 Edit: I normally don't react to downvotes but this is a direct quote. Larger context: this was also the all-time highest monthly temperature in the 1880–2015 record, at 61.86°F (16.61°C), surpassing the previous record set in 1998 by 0.14°F (0.08°C)

How exactly do they do a fair comparison between 1880 and today? I'm assuming the temperature readings today are very accurate, but how accurate were the measuring devices going back in history, and their standards for taking temperature? Most of the thermometers I have in my house are +- 2F, which would eliminate the differences entirely.

Re: July 2015 was warmest month ever recorded

#24
post #8
post #3

Since 1880 Edit: I normally don't react to downvotes but this is a direct quote. Larger context: this was also the all-time highest monthly temperature in the 1880–2015 record, at 61.86°F (16.61°C), surpassing the previous record set in 1998 by 0.14°F (0.08°C)

[deleted]

It's pretty easy to understand why it's being downvoted. It doesn't contribute to the conversation--it's a pedantic tangent that isn't any more interesting than noting that (1) the surface of the Earth used to be molten and (2) all matter in the known Universe was a lot hotter during the big bang. Is that relevant?

Re: July 2015 was warmest month ever recorded

#25
post #3

Since 1880 Edit: I normally don't react to downvotes but this is a direct quote. Larger context: this was also the all-time highest monthly temperature in the 1880–2015 record, at 61.86°F (16.61°C), surpassing the previous record set in 1998 by 0.14°F (0.08°C)

So is that a long time or a little?

Re: July 2015 was warmest month ever recorded

#26
post #3

Since 1880 Edit: I normally don't react to downvotes but this is a direct quote. Larger context: this was also the all-time highest monthly temperature in the 1880–2015 record, at 61.86°F (16.61°C), surpassing the previous record set in 1998 by 0.14°F (0.08°C)

How exactly do they do a fair comparison between 1880 and today? I'm assuming the temperature readings today are very accurate, but how accurate were the measuring devices going back in history, and their standards for taking temperature? Most of the thermometers I have in my house are +- 2F, which would eliminate the differences entirely.

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 comparable to modern 2-3 day weather forecasts in terms of accuracy, even with the limited data available (things like barometric pressure readings from ships).

I'm not sure about the technology used at the time, but the basic answer to your question that that they had a lot more thermometers than you expect, distributed globally too. And as we're discussing global averages, the noise about +-2F in your house isn't really the same problem.

Edit: Here's a neat 100-year reanalysis paper if you're interested. Abstract link here, full pdf available on the page: http://journals.ametsoc.org/doi/abs/10.1175/BAMS-87-2-175. "Feasibility of a 100-Year Reanalysis Using Only Surface Pressure Data"

Re: July 2015 was warmest month ever recorded

#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?

Re: July 2015 was warmest month ever recorded

#30
post #8
post #3

Since 1880 Edit: I normally don't react to downvotes but this is a direct quote. Larger context: this was also the all-time highest monthly temperature in the 1880–2015 record, at 61.86°F (16.61°C), surpassing the previous record set in 1998 by 0.14°F (0.08°C)

[deleted]

If so, it's not nearly to the extent of modern temperature increases, and modern CO2 increases are certainly not part of a preindustrial trend.
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