No, thankfully, that didn't happen in Holocene maximum, when temps were approx 1 degree c. warmer than they are now.
Although you say "much" warmer. Is that empirical data?
But at temps 2 degrees higher than now, the permafrost will melt. *We're that close! *
And there is evidence that the maximum didn't bring that high temps to the Arctic in the past, and that the Arctic is warming at a faster rate than other parts of the globe.
http://www.usmessageboard.com/environment/321121-study-shows-unprecedented-warmth-in-arctic.html
There is 1200 Gton of methane in the Arctic permafrost, compared to 5 Gton in the atmosphere. *The potential threat is real.
Get ready prepper!
Oh, they were much warmer than that... You need to get your facts straight there mister.
"Abstract
We analyze the global variations in the timing and magnitude of the Holocene Thermal Maximum (HTM) and their dependence on various forcings in transient simulations covering the last 9000 years (9 ka), performed with a global atmosphere-ocean-vegetation model. In these experiments, we consider the influence of variations in orbital parameters and atmospheric greenhouse gases and the early-Holocene deglaciation of the Laurentide Ice sheet (LIS). Considering the LIS deglaciation, we quantify separately the impacts of the background melt-water fluxes and the changes in topography and surface albedo.
In the analysis we focus on the intensity of the maximum temperature deviation relative to the preindustrial level, its timing in the Holocene, and the seasonal expression.
In the model, the warmest HTM conditions are found at high latitudes in both hemispheres, reaching 5 °C above the preindustrial level, while the smallest HTM signal is seen over tropical oceans (less than 0.5 °C). This latitudinal contrast is mostly related to the nature of the orbitally-forced insolation forcing, which is also largest at high latitudes, and further enhanced by the polar amplification. The Holocene timing of the HTM is earliest (before 8 ka BP) in regions not affected by the remnant LIS, particularly NW North America, E Asia, N Africa, N South America, the Middle East, NE Siberia and Australia. Compared to the early Holocene insolation maximum, the HTM was delayed by 2–3 ka over NE North America, and regions directly downwind from the LIS. A similar delay is simulated over the Southern Ocean, while an intermediate lag of about 1 ka is found over most other continents and oceans. The seasonal timing of the HTM over continents generally occurs in the same month as the maximum insolation anomaly, whereas over oceans the HTM is delayed by 2–3 months. Exceptions are the oceans covered by sea ice and North Africa, were additional feedbacks results in a different seasonal timing. The simulated timing and magnitude of the HTM are generally consistent with global proxy evidence, with some notable exceptions in the Mediterranean region, SW North America and eastern Eurasia."
Global characterization of the Holocene Thermal Maximum
And....
The Holocene thermal maximum and late-Holocene cooling in the tundra of NE European Russia
Salonen, JS; Seppa, H; Valiranta, M; Jones, VJ; Self, A; Heikkila, M; ... Yang, HD; + view all (2011) The Holocene thermal maximum and late-Holocene cooling in the tundra of NE European Russia. QUATERNARY RES , 75 (3) 501 - 511. 10.1016/j.yqres.2011.01.007.
Full text not available from this repository.
Abstract
To investigate the Holocene climate and treeline dynamics in the European Russian Arctic, we analysed sediment pollen, conifer stomata, and plant macrofossils from Lake Kharinei, a tundra lake near the treeline in the Pechora area. We present quantitative summer temperature reconstructions from Lake Kharinei and lake Tumbulovaty, a previously studied lake in the same region, using a pollen-climate transfer function based on a new calibration set from northern European Russia.
Our records suggest that the early-Holocene summer temperatures from 11,500 cal yr BP onwards were already slightly higher than at present, followed by a stable Holocene Thermal Maximum (HTM) at 8000-3500 cal yr BP when summer temperatures in the tundra were ca. 3 degrees C above present-day values. A Picea forest surrounded Lake Kharinei during the HTM, reaching 150 km north of the present taiga limit. The HIM ended with a temperature drop at 3500-2500 cal yr BP associated with permafrost initiation in the region. Mixed spruce forest began to disappear around lake Kharinei at ca. 3500 cal yr BP, with the last tree macrofossils recorded at ca. 2500 cal yr BP. suggesting that the present wide tundra zone in the Pechora region formed during the last ca. 3500 yr. (C) 2011 University of Washington. Published by Elsevier Inc. All rights reserved.
UCL Discovery - The Holocene thermal maximum and late-Holocene cooling in the tundra of NE European Russia
There are plenty more should you choose to educate yourself properly.