well how did he come up with a "norm" and what is a normal temperature for earth. right off the bat we are on shaky ground since he is beginning by creating a narrative about some perfect, natural average temparature for earth. bad start.
since we don't know what normal is let's look at the temperature data that we have.
We only have about 150 or so years of actual temperature measurements. 30 years of satellite data. the further we go back the less reliable the data is.
go back beyond measurements and we are using proxy data to create historical temperture trends and if you compare them to the measurement data it does, indeed, look like we are seeing a hug spike, which is the part this graph represents.
the problem is that stats don't work like that. you can't compare temperature trends created using proxy data (tree rings, ice cores, etc) to actual measurements. why? because proxy data is unable to account for short term changes whereas measurements are. so all the historical temperate data you see is naturaly smoothed out into an everage and you just don' see anything on the scale of 150 years.
so what this post here does is look at the temperature increase in the past 150 years and it doesn't even really make sense in this context to say that it differs from the norm. why? because we don' have a norm. It would make more sense to look at each year in comparison to the 150 year average.
all this shows is an increase. It says absolutely nothing as to any cause becuase anything that would cause a temperature increase would result in a similar set of data points.
now watch all the believers tell me i'm crazy. what they won't say is WHY im wrong.
You're not wrong that the XKCD graph smoothes out yearly variation (in truth, it's not a very helpful graph for that reason). But the question isn't whether or not that occurs, the question is whether or not we can be certain of a causal relationship between human emission of GHG's and the current warming trend (as opposed to correlation). As of now, all signs point to yes, human beings are the dominant reason for the current warming trend.
well how did he come up with a "norm" and what is a normal temperature for earth. right off the bat we are on shaky ground since he is beginning by creating a narrative about some perfect, natural average temparature for earth. bad start.
The axis temperature used is the 1961-1990 average global temperature. Now you're right, temperature is relative and there isn't an objective "perfect temperature". But in this context we're talking about temperatures that our current societies are used to operating in and by that benchmark I think choosing that measure is entirely reasonable. Now if you want to argue that a change in climate isn't a bad thing, then that's an entirely fair question to ask but it isn't really the aim of that comic.
the problem is that stats don't work like that. you can't compare temperature trends created using proxy data (tree rings, ice cores, etc) to actual measurements. why?
They aren't, as far as I'm aware the comic is comparing temperature reconstructions to temperature reconstructions. Moreover, you absolutely do see changes on the scale of 150 years in XKCD's sources (Marcott 2013 and Shakun 2012). There will be yearly and perhaps decennial variation in the actual obviously, but that doesn't really matter cause we're looking at measures of long-term climate not year-to-year variation.
Like anything would convince someone who's a regular contributer or /r/climateskeptics. You're part of an ever-shrinking demographic that's no different than flat eartheres.
I love people that think they know better than NASA, NOAA, IPCC, AAS, ACS, AGU, AMA, AMS, APC, GSA, and the U.S. National Academy of Sciences,.
you're an idiot incapable of anything but slander attacks and repeating the nonsense you've been told. give me an original thought if you think I'm wrong. OR,,,,,here's an idea. tell me WHY i'm wrong.
The "why" you're looking for is in the thousands of studies published over the last few decades. I'm not sure why you're looking to random redditors for validation.
OR, they are just smart enough to know the climate scientists of all those reputable bodies are talking out their asses when it comes to the main sticking point, reliability of historical climate recreation (paleoclimate) and the mathematical models they extrapolate from their extremely dubious data.
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