1 - the title says 1948, not 2048

2 - meaningful comparisons are done with 30-year baselines, not a single year. Maybe you should benefit from your typo in the title and take the 1948-1978 average and then compare that to 2048.

Thanks @BrunoParga , appreciate it.

1. Yeah, my blunder there. I've fixed it.

2. I think the Q is ok here. If you look at the description you'll see the calculation method. It's a linear fit over the time period so there isn't the problem of having volatility at the start or end point. LMK

@Ronan I don't really understand the calculation method, but what little I understand seems to suggest that you are taking November 1978 as your starting point, rather than the average of a 30-year period as is usual. But maybe this is not so, I don't know.

@BrunoParga the method is to take all of the data from the period of 1978 to 2048 and fit a line to them. Using that line as a basis, a temperature increase over the period can be calculated.

This is the simplest (most robust) way to compute an increase over a given time period as it involves finding the closest fit to all datapoints over the period (as opposed to having to pick a specific time period for averaging at the start and at the end).

@Ronan sure, now I see how that smoothes out any big discrepancies in the endpoints from the trend line.

It is just not, to my knowledge, how this is generally done, and I think there is more value to predicting values that are usual.

@BrunoParga yeah I see your point. It can be good to stick to standards.

The issue with standards here is that to get a 30 year average for around the year 1950, we would need to wait on 15 years after that.

But yeah, maybe there's a separate worthwhile poll here where I compare the average over the years 2035-2065 (with the poll resolving in 2065) compared with the average over 1978-2008. Let me see what other good feedback I get before making another poll just yet. Thanks.

@Ronan AFAIK the 30-year average is only for the reference period; each individual year is compared to that.