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Tracking Crucial Metrics of Earth's Global Warming

climatechangetracker.org

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Re: Tracking Crucial Metrics of Earth's Global Warming

#41

Post by kkjjkgjjgg »

esarbe wrote: post #24
kkjjkgjjgg wrote: post #3

I really dislike the use of the word "anomaly" in climate change circles. It may be technically correct, but it feels like propaganda. All it is is the difference to the average of an arbitrarily chosen time frame. It would actually be strange if temperatures where exactly like the average all the time, so calling it an anomaly if they are different from the average really seems misleading. Again, it may be the techn…

What are "climate change circles" supposed to be? You mean the people not willfully blind of the facts? Sure, must be propaganda.

I mean people trying to show or prove the effects of climate change. Whether you believe in it or not, there supposedly are specialists working in that area. At least that is usually the argument, that there are experts who worked it all out whom we should listen to. So I think those can be called "climate change circles".

Re: Tracking Crucial Metrics of Earth's Global Warming

#42

Post by User23 »

tonmoy wrote: post #13
jimmydorry wrote: post #7

Earlier quoted context omitted.

To add to your post, where and how did they determine that 30 years was the appropriate time scale to use? >The value we show is a 30 year rolling average of temperature change. We have chosen that long term trend because it fits the time scale of the climate and its changes.

There isn’t enough temperature record around before that timeframe to estimate an accurate global average. You can still see the effects of temperate indirectly

Arguably, the quality record only began with the launch of satellites. How much can we really trust some weather station in the middle of Montana from 1880? And of course pre-satellite the data for the southern half of the globe is relatively sparse.

When it comes to CO2 in particular, there are things like ice cores and plant fossil stomata that gives us some understanding over geological timeframes, but that's very different from a thirty year average.

Re: Tracking Crucial Metrics of Earth's Global Warming

#43

Post by SiempreViernes »

landemva wrote: post #34
davidw wrote: post #22

Earlier quoted context omitted.

My understanding is that it's changing at a faster rate than previous non human caused shifts. That's the anomaly.

The fastest shifts occurred after large volcanic activity. And cold summers for a few years then led to crop failures. Am really interested in more analysis of correlation of reduced sunspot activity and then increased volcanic activity. It appears to be a fascinating correlation. Update - The mammoths with undigested grass in their stomachs, which froze to death while eating, may indicate magnetic pole flip creates…

> Am really interested in more analysis of correlation of reduced sunspot activity and then increased volcanic activity. It appears to be a fascinating correlation.

Sad to see the sunspot conspiracies still alive and kicking. Here, have some 14 year old news about how they don't matter enough to bother with in discussions about today's climate: https://www.nature.com/articles/nature05072

Re: Tracking Crucial Metrics of Earth's Global Warming

#44

Post by SiempreViernes »

zdragnar wrote: post #27
laichzeit0 wrote: post #25

Earlier quoted context omitted.

I have a feeling that the climate change charts induce a similar knee jerk reaction as IQ scores or vaccines. Most people have an ideology they subscribe to and will argue using facts and reason in order to support it. I have yet to witness a religious person be reasoned into atheism. I suspect the applies for the above mentioned categories, whatever side of the fence the person happens to be on.

Charts and visualisations are a great way to trick people. Not only is the source data obscured (and so readily cherry picked) but it opens up all sorts of tricks around visual perception. I also suspect most people yet to be convinced will immediately think back to Al Gore's infamous hockey stick chart when presented with visual simplifications of deeply complex climate data. At the heart of the matter, looking at s…

Surely you mean the infamous lies about the Mann 1999 "hockey stick"? The Mann 1999 results are correct (see for instance https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5505119/figure/... for confirmation) and the graph doesn't do anything more nefarious than the plot summaries you'll see in imdb: it summarises a complicated thing.

Re: Tracking Crucial Metrics of Earth's Global Warming

#45

Post by beowulfey »

kkjjkgjjgg wrote: post #38
beowulfey wrote: post #10

Earlier quoted context omitted.

It is a comparison of two averages, not of a single temperature to an average. A changing average suggests a change in the underlying factors at play, because while a single observation may not ever match the average as you say, a system in equilibrium should not see the average changing. This is why it is called anomalous: the mean is changing continuously. It’s a crude metric but in the framework of the analysis (p…

I don't think that explanation is correct. The average temperature of a year is just a specific way to take a measurement. Comparing it to an average of averages over several years is then the same as comparing a measurement to an average of measurements. That the climate should never see averages changing seems obviously false. There clearly are cycles that last longer than a year, for example, as several ice ages c…

Yes, the averages can and do change—that is my point. A changing average suggests something about the system is changing. It doesn’t need to be compared to preindustrial temperatures, but it is a good baseline because the temperature variation (as shown in the chart) was pretty small within that timeframe compared to the changes we are seeing today.

Re: Tracking Crucial Metrics of Earth's Global Warming

#46

Post by beowulfey »

PeterisP wrote: post #29
beowulfey wrote: post #10

Earlier quoted context omitted.

It is a comparison of two averages, not of a single temperature to an average. A changing average suggests a change in the underlying factors at play, because while a single observation may not ever match the average as you say, a system in equilibrium should not see the average changing. This is why it is called anomalous: the mean is changing continuously. It’s a crude metric but in the framework of the analysis (p…

I would consider that "anomaly" would refer to something unusual or unexpected, an outlier, or a weird unexplained occurrence contrary to our expectations, or a one-off deviation followed by a return to the norm. On the other hand, a continuously changing mean or a systematic pattern IMHO is not an "anomaly"; something can't be unusual for long - if something has become or is clearly going to become usual, then it's…

Yes, this is a good point. It is only anomalous if we expect the mean temp to remain relatively constant—it is definitely dependent on the conceptual framework!

Re: Tracking Crucial Metrics of Earth's Global Warming

#47

Post by kkjjkgjjgg »

7952 wrote: post #16
kkjjkgjjgg wrote: post #3

I really dislike the use of the word "anomaly" in climate change circles. It may be technically correct, but it feels like propaganda. All it is is the difference to the average of an arbitrarily chosen time frame. It would actually be strange if temperatures where exactly like the average all the time, so calling it an anomaly if they are different from the average really seems misleading. Again, it may be the techn…

Comparing to a baseline is useful because that is what our culture, technology and habits are adapted to. And the conditions that ecosystems can be based on. An increase in temperature away from that has consequences that need to be understood.

I have nothing against the comparison, just with the choice to call the deviation from the average "anomaly".

I think in one step you should present the data, making sense of it is another step. Technically "anomaly" is just used for the distance to the average of some chosen timeframe, but in common language terms it suggests something unnatural is going on. As I said, it would be unnatural to have exactly the average temperature every year. (It may still be such an extreme difference that it is unnatural, but that is not how they use the word anomaly. It just means different from the average).

Re: Tracking Crucial Metrics of Earth's Global Warming

#48

Post by kkjjkgjjgg »

User23 wrote: post #42
tonmoy wrote: post #13

Earlier quoted context omitted.

There isn’t enough temperature record around before that timeframe to estimate an accurate global average. You can still see the effects of temperate indirectly

Arguably, the quality record only began with the launch of satellites. How much can we really trust some weather station in the middle of Montana from 1880? And of course pre-satellite the data for the southern half of the globe is relatively sparse. When it comes to CO2 in particular, there are things like ice cores and plant fossil stomata that gives us some understanding over geological timeframes, but that's very…

Even if the measurements from the middle of Montana is correct, I could imagine there are different ways to extrapolate to average global temperature from just a few points of measurements. In the end, it will just be another estimate.

Re: Tracking Crucial Metrics of Earth's Global Warming

#49

Post by ximeng »

kkjjkgjjgg wrote: post #39
polotics wrote: post #8

Earlier quoted context omitted.

How and why does it feel like propaganda? What is being compared is averages with and without CO2 induced forcing.

No they picked a certain time frame and compare to the average temperature of that time frame. Nothing more, nothing less. I think the reference time frame is some 20 year period in the end of 20th century, but not sure if I remember it correctly.

From the site the baseline is very clearly stated:

What is the Yearly Average Temperature Anomaly?

It is the difference between the average yearly global surface temperature and its pre-industrial baseline. The pre-industrial baseline is calculated as the average temperature from 1850 till 1900. The value for the current year is actually the average for the last 12 months, for example in June we include values since the previous July.

I really don't understand what your issue is with the terminology. Are you suggesting there is no change from the norm? Propaganda as in there is a political agenda to presenting this data? Would that be that the data is wrong, if so on what basis? Or that the data is irrelevant and it is being presented as relevant?

Global temperature changes seems very relevant to me. This site is also just presenting data, the language is pretty neutral and in line with the common use of anomaly ("something that deviates from what is standard, normal, or expected") given the baseline they have stated, as well as the wikipedia article you link. The main issue I see from the wikipedia article is that these are not "standardised anomalies" - but the site is not claiming to provide these.

If your argument were that they should provide more data I could see that, although it's marked as version 0.1 so perhaps that's a bit harsh. If it's just that they're using the wrong word, then that's not very compelling to me.

Re: Tracking Crucial Metrics of Earth's Global Warming

#50

Post by User23 »

kkjjkgjjgg wrote: post #48
User23 wrote: post #42

Earlier quoted context omitted.

Arguably, the quality record only began with the launch of satellites. How much can we really trust some weather station in the middle of Montana from 1880? And of course pre-satellite the data for the southern half of the globe is relatively sparse. When it comes to CO2 in particular, there are things like ice cores and plant fossil stomata that gives us some understanding over geological timeframes, but that's very…

Even if the measurements from the middle of Montana is correct, I could imagine there are different ways to extrapolate to average global temperature from just a few points of measurements. In the end, it will just be another estimate.

That reminds me of a thought experiment. Suppose you want to accurately measure the average temperature of a company cafeteria. How many thermometers do you need and where do you place them? Do you keep them in fixed locations or move them?

That thought experiment is readily adapted to other spaces, such as a high school gymnasium or the state of Iowa.

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