This is my theme–even if the warmers were right, and there is a warming effect from whatever cause, warm is good for the living habitants of the planet, plants, insects, animals, fish, humans. The planet is more hospitable in more regions when it is warmer.
I am something of an expert on these warm is good, cool is bad things, so I must introduce this paper by two Hong Kong researchers with some caveats.
First– the urban island effect is at work here, producing the warming that is reported.
Second– the general improvement in infrastructure that one would expect for housing, air conditioning, food and water, as well as sewerage would cause a decline in elderly mortality that would be apparent in the studies and so differences might be impacted in the right direction for cold and heat related deaths.
Third– Also, considering a less than one degree difference in temp? Really? What plausible explanation could be posited to make changes in temp that are with the error rate of the temp record a cause of change in death rates?
Four–And How would one separate out the effect of such slight temperature differences from the effects mentioned above, that would include improvments in medical care over time?
I would assert that the better method is to assess summer versus winter death rates and see if that difference changes when assessed against winter and summer temps.