2019 Temperatures

[bdgwx]

2 hours ago, TriPol said:

But how accurate were those thermometers back then in the 1,000 stations in 1880? 

Certainly not as accurate as today. But here's the cool thing about math. Trivially if a thermometer has an error of say 2C and there are 1000 thermometers then the error of the mean is only 2/sqrt(1000) = 0.06C. In reality it's far more complicated than that. After it is all said done surface datasets like GISTEMP publishes an error of about 0.10C before WWII and 0.05C after for the global mean temperature. The error envelope expands the further back in the 1800's you go.

Berkeley Earth actually has some in depth papers on how it works and how the uncertainty is determined. Fair warning...it's thick stuff.

http://berkeleyearth.org/static/papers/Methods-GIGS-1-103.pdf

http://berkeleyearth.org/static/pdf/methods-paper-supplement.pdf

[chubbs]

On 1/13/2020 at 12:28 PM, frankdp23 said:

This is a general question that just popped into my head when looking at my weather channel calendar.  The one fact on it for Jan 25th was stating that the global land/ocean surface temp in Jan 2019 tied 2007 for the 3rd warmed (going back to 1880).  How many global stations (I'm not sure what they are really called) were there in 1880 compared to now? Was there 1000 stations back then, and 10000 now?  Do they try to use the same number?  I'm guessing if they are using that stat, they aren't using sat temps?  Thanks for the input in advance. 

You don't have to go back very far to for record high global temperatures, December for example.

[FPizz]

12 hours ago, etudiant said:

It is a serious issue that the researchers recognize by widening the error bars on the older data.

There are so many changes to take into account, in the instrumentation as well as the environmental transformation over the past 140 years. Add to this that many places were not monitored consistently, so putting it all together is a massive task involving lots of judgments. For instance, a site that has a continuous record since 1880 is valuable, as there are not that many, but that location may have gone from rural to midtown during that interval.

There has been an effort to select a relatively small number of stations, in the 1000 range iirc, which are deemed representative, so many fewer stations are used for the more recent data than are available. 

Thank you!  I was wondering how they did come up with it.  I'm guessing too that back then, humans had to record the temps daily (how often though really, every hour, 2x a day?) vs now everything is automated.  Having monitoring 24/7 vs monitoring maybe 2x a days can cause issues too.  Pretty interesting how they do it. 

[TriPol]

9 hours ago, bdgwx said:

Certainly not as accurate as today. But here's the cool thing about math. Trivially if a thermometer has an error of say 2C and there are 1000 thermometers then the error of the mean is only 2/sqrt(1000) = 0.06C. In reality it's far more complicated than that. After it is all said done surface datasets like GISTEMP publishes an error of about 0.10C before WWII and 0.05C after for the global mean temperature. The error envelope expands the further back in the 1800's you go.

Berkeley Earth actually has some in depth papers on how it works and how the uncertainty is determined. Fair warning...it's thick stuff.

http://berkeleyearth.org/static/papers/Methods-GIGS-1-103.pdf

http://berkeleyearth.org/static/pdf/methods-paper-supplement.pdf

What if all of the thermometers had bad data back then? Or not the thermometers, but the people reporting the temps weren't the most accurate? And we weren't even measuring ocean temps back then, just temps at stations, which were probably in cities. We had no idea if there was an El Nino or La Nina in 1885. We can only guess based off of observations. 

But, let's assume you're right. Let's assume that the average temperature, globally has increased by 2C since 1880 and that we're hotter than we've been in a long time. Well, what were the conditions like thousands of years ago? Seems to me that human beings survived this pretty well. 

I don't disagree that that earth is warming, I disagree with the hysteria surrounding it. "We only have 10 years to save civilization before we go extinct!" C'mon. 

[bdgwx]

20 minutes ago, TriPol said:

What if all of the thermometers had bad data back then? Or not the thermometers, but the people reporting the temps weren't the most accurate? And we weren't even measuring ocean temps back then, just temps at stations, which were probably in cities. We had no idea if there was an El Nino or La Nina in 1885. We can only guess based off of observations. 

There are many potential sources of error including instrument bias, station moves, station sighting changes, time-of-day of observation, urban heat island effect, human element, etc.

Ocean temperature datasets like ERSST and HadSST go back well into the 1800's as well. They are used as inputs into the global mean surface temperature (GMST) datasets as well.

We have reconstructions of the ENSO cycle going back hundreds of years. The ENSO phase was positive (El Nino) in 1885 and into 1886.

Speaking of cities and the potential for the urban heat island effect...Berkeley Earth concluded that the UHI bias was flat to even negative since 1950 during the period in which the anthroprogenic influence is most acute.

33 minutes ago, TriPol said:

But, let's assume you're right. Let's assume that the average temperature, globally has increased by 2C since 1880 and that we're hotter than we've been in a long time. Well, what were the conditions like thousands of years ago? Seems to me that human beings survived this pretty well. 

Berkeley Earth shows that the GMST increased about 1.0C since 1880.

Temperature proxies like those derived from ice cores, tree ring analysis, etc. can provide insights into the GMST going back millions of years.

[LibertyBell]

2 hours ago, TriPol said:

What if all of the thermometers had bad data back then? Or not the thermometers, but the people reporting the temps weren't the most accurate? And we weren't even measuring ocean temps back then, just temps at stations, which were probably in cities. We had no idea if there was an El Nino or La Nina in 1885. We can only guess based off of observations. 

But, let's assume you're right. Let's assume that the average temperature, globally has increased by 2C since 1880 and that we're hotter than we've been in a long time. Well, what were the conditions like thousands of years ago? Seems to me that human beings survived this pretty well. 

I don't disagree that that earth is warming, I disagree with the hysteria surrounding it. "We only have 10 years to save civilization before we go extinct!" C'mon. 

it doesn't matter if they were hotter then than they are now- the rate of change now is what matters.  And if you go back before human history, mass extinction events resulted because of sudden changes- and we have a mass extinction event underway right now.

 

[bobjohnsonforthehall]

46 minutes ago, LibertyBell said:

it doesn't matter if they were hotter then than they are now- the rate of change now is what matters.  And if you go back before human history, mass extinction events resulted because of sudden changes- and we have a mass extinction event underway right now.

 

Really? A mass extinction event? Really?

 

No I mean...Really?

[LibertyBell]

42 minutes ago, bobjohnsonforthehall said:

Really? A mass extinction event? Really?

 

No I mean...Really?

Yep.  I'm actually shocked you didn't know a mass extinction event was going on.

https://cosmosmagazine.com/palaeontology/big-five-extinctions

Biologists suspect we’re living through the sixth major mass extinction. Earth has witnessed five, when more than 75% of species disappeared. Palaeontologists spot them when species go missing from the global fossil record, including the iconic specimens shown here. “We don’t always know what caused them but most had something to do with rapid climate change”, says Melbourne Museum palaeontologist Rolf Schmidt.

[bobjohnsonforthehall]

50 minutes ago, LibertyBell said:

Yep.  I'm actually shocked you didn't know a mass extinction event was going on.

https://cosmosmagazine.com/palaeontology/big-five-extinctions

Biologists suspect we’re living through the sixth major mass extinction. Earth has witnessed five, when more than 75% of species disappeared. Palaeontologists spot them when species go missing from the global fossil record, including the iconic specimens shown here. “We don’t always know what caused them but most had something to do with rapid climate change”, says Melbourne Museum palaeontologist Rolf Schmidt.

This is what I mean by science being so unscientific. Biologists don't understand what "mass extinctions" are I guess? Mass extinctions go far beyond a species level to entire genera, families, orders, classes and sub-phyla. Species extinction does not equate to "mass extinction". It also doesn't take into account new species that are forming or being discovered all the time. 

So don't be shocked. Understand that a mass extinction is not really happening.

[LibertyBell]

1 hour ago, bobjohnsonforthehall said:

This is what I mean by science being so unscientific. Biologists don't understand what "mass extinctions" are I guess? Mass extinctions go far beyond a species level to entire genera, families, orders, classes and sub-phyla. Species extinction does not equate to "mass extinction". It also doesn't take into account new species that are forming or being discovered all the time. 

So don't be shocked. Understand that a mass extinction is not really happening.

The reason that they are so worried, I think, is that they are keeping track of certain "keystone" species that other creatures are reliant upon and whose numbers are reduced (one of them being starfish).  Some species are more important than others as you probably know (this is why the reduction in pollinator species is so important.)

 

[bobjohnsonforthehall]

10 minutes ago, LibertyBell said:

The reason that they are so worried, I think, is that they are keeping track of certain "keystone" species that other creatures are reliant upon and whose numbers are reduced (one of them being starfish).  Some species are more important than others as you probably know (this is why the reduction in pollinator species is so important.)

 

Perhaps, but you are still not looking at a "mass extinction". This is still at the species level. The term "mass extiction" carries a lot of weight and thus is thrown around to scare people. A better, more accurate term could be used to describe the goings on, but it won't be, because it wouldn't scare enough people. 

So "mass extinction" we get I suppose. Correct or not.

[bdgwx]

Carbon Brief posted their 2019 State of the Climate Report.

https://www.carbonbrief.org/state-of-the-climate-how-the-world-warmed-in-2019