Summation: Local cooling climate changes, since the last ice age seem relatively common and all seem to cause significant harm to human population. But I can't find instances of the reverse, warming climate changes that caused harm. If anything, the correlation seems reversed, warming climate change brings benefits. (Note: Droughts to not indicate warming.)
Are there any known or suspected historical i.e. Holocene climatic warming associated with negative impacts on human populations?
This one caught me by surprise. I had assumed episodes of destructive warming would be common and well documented.
I am reading The Great Famine: Northern Europe in the Early Fourteenth Century by Medieval scholar William Chester Jordan. The book regards a massive famine that hit Western/Northern Europe 1315-1322. Until recently, the Great Famine was overshadowed by the "Great Mortality" pandemic episode of the Black Death which struck 1346–53. Computerization of period sources in the last 20 years has allowed researchers to correlate much wider patterns than in the past and the event is now know to have been much wider in area and of longer duration than realized.
Besides the scale, what makes the Great Famine possibly unique is that it was caused by three or more years of continuous rain i.e. it rained roughly 9 out of every 10 days, Spring, Summer and Fall.
The rain essentially drowned the seedlings in spring, the roots in summer, then rotted crops in the fields towards fall. In addition, the extraordinary wet conditions caused a "murine" an outbreak of diseases in almost all domestic animals but particularly cattle e.g. Hoofed animals often had their hooves (which are just giant toenails) so constantly immersed that eventually they just sloughed off. Other's died of water born illnesses.
I was intrigued by the event because I assumed before reading the book that the catastrophe must have been a localized example of the "The Big Sog" outcome predicted by some climate models in which the increase in world temperatures leads to significantly higher humidity world wide which causes incessant rain. I knew that the effected years fell into the Medieval Climate Anomaly which definitely represented a sustained warming in Europe and likely most of the Northern Hemisphere.
However, the chronicles, various accounting records and climate proxies all show a dramatic cooling, with brutal winters of intense cold, deep snows and ice packs forming on the Northern shores Europe. The overall climate/weather-patterns had shown a general but widely oscillating cooling pattern since the late-1200s. After the 1320s, Europe (at least) slipped into "The Little Ice Age".
It was this cooling that allowed the Black Death to spread by altering the way in which the Y. Pestis bacteria clump inside the fleas that carry it. The same dynamic of cooling, rain, harsh winters and plague outbreak, occurred in 542 in the Mediterranean world during when several years of cooling probably caused by a volcanic eruption, reduced harvest, drove nomads southward and nearly destroyed the Byzantine and Sasanian empires.
During the Medieval Anomaly it appears that the climate of MesoAmerica, North America west of the Sierras grew dryer with years and possibly decades of drought conditions. However, the overall temperatures seemed to have cooled.
Drought conditions can cause higher peak daytime temperatures because of the loss of cloud cover, but these peaks are offset by nighttime lows by the same mechanism, just as occurs in deserts. The actual heat content of the atmosphere, its enthalpy, which drives weather and climate, actually decreases because most of the heat is held in the atmospheric humidity and the biomass. It's easy to see how cooling can cause droughts.
I'm looking for the kind of increase in enthalpy predicted for world wide by current climate models.
If such events are unknown, that would be a separate question.