We've all seen scientifically-illiterate media reports blaming every heat wave and drought on global warming. Regional weather events with timescales of days to years are not equivalent to global weather/climate changes with timescales of decades to centuries.
Again, that is not apples-to-apples comparison. It is very hard (practically impossible) to show any given localized weather event (hurricane, tornadoes, draught) or its intensity is caused by a change in global temperature. But geography temperatures are
by definition included in the global temperature. Mathematically, the global temperature is the average of the temperatures over the globe. So when the global temperature goes up or down,
it means that some locations are going up or down (mean value theorem of calculus).
So we can absolutely say that if global temperatures plummet, that its plummeting in China and US are part of that trend.Now interestingly, there is a small, non-zero chance that all the change is over sea rather than land. So, technically global temperature could plummet without the temperature in any country following suit. Out of curiosity I pulled 20 years (and 2018 to date) of monthly global and land temp data from the satellite sets. I subtracted the average of the data from the respective values to create temperature anomolies. I then regressed them to each other. Here is what the scatter looks like.
So, we can clearly see that generally the land component of global temperature and overall global temperature go in step (correlation 0.85 so about 70% of variance in land temp reflects global trend).
We already had that discussion in another thread. Your graph there shows that global temps are down from their record highs of 2 years ago, and I find this completely unsurprising because the graph is full of similar ups-and-downs lasting several years.
While it is true that 2016ish was relatively high (actually December 2016 wasn't very high as we will see), this statement is disengenuous as it makes it seem that it is an above average year, just lower than the previous couple. That is not the case as I noted previously. If the trend from the rest of the year continues for December (and it actually looks like it will be an even bigger drop than previous months) the land temperatures around the globe will be well below average. Here is the trend data for the last 20 years:
As you can see, these temperatures are very well distributed around zero (the average). Here is a histogram:
Now here is a key chart pulling out just the December data (recalculating the anomolies for that subset). I put a red dot where if the trend continues December 2018 will fall (we will have the actual data first week of January).
Net:
Global temperatures are plummeting.
Land Temperatures are moving in line with this global trend.
This is not just a "drop off record", it is trending below two decade averages.
We are seeing this drop manifest in multiple places around the globe (China, US, etc).
It would be prudent to prep for colder weather (and enjoy the incredible videos of what happens at -40 degrees and below!)
