I guess you will be interested in real answers as obviously the denier who posted the matching question won't be.
I find it interesting he would post such a question given deniers other pet hate is proxy data, and the temperature record over 2500 years is based on proxy data, but then denier tend to forget what they said yesterday when trying to push today's excuse.
As I said in the other question which had a link to story and photo from Jo Nova, it does not need to have been warmer for ice to recede as far as it seems to have it just needs more time, ice is currently retreating as the denier story unwittingly admits, it is certainly possible small glaciers may have retreated further in the same sort of temperature range as we have now if it had stayed as warm as it is now but for a longer period of time, that is already built into current estimates even if we brought our current emissions under control.
I seem to recall a snide comment about polar bear in the other question as well, I find these revealing about the mindset of deniers, given the nature of were polar bears live we have little real evidence on their past population as most would die on the sea ice and be lost, so there is no way to tell if they did suffer a marked population drop associated with this decline in ice.
As can be seen in the population increase in PB's when hunting was reduced or other animals like Rhino, they can recover fairly quickly, but certainly (despite denier fictional claims) the current evidence is that their numbers are dropping again.
As for temperatures and the proxy record, Ms Nova is at best a pseudo scientist and in reality just a blogger. The actual proxy data shows (in averaged form) it was warmest ~8000 years ago, this would be in line with previous interglacial in a short sharp spike in temperature followed by a long slow decline back to glacial conditions that would actually fit the story Ms Nova is trying to sell her denier chumps.
Ice would advance slowly (as it retreats slowly) and swallow trees. glaciers should have expanded slowly given what the proxy data shows as the average from ~8000ya to around 200ya show an overall cooling, but with fluctuation.
http://en.wikipedia.org/wiki/File:Holoce...
At least until the start of the industrial revolution, when the long term slow decline seems to have stopped, if you look at the 2004 level on the above graph the comparison is stark we are above even the level of 8000 years ago. of course in nature that level fluctuated with the conditions.
What all this means for deniers theory's that ice is not retreating seems to have been forgotten by this particular denier and Jo Nova, given their story presents evidence of things exposed that are 2500 years old, it's the usual whoops from denier central.
Edit we could go with the musing of deniers on the Halocene? i.e. Holocene or the Roman Warm period, but again the data we have on these is based on proxy data, which on Tuesdays and Thursdays deniers tell us can't be trusted, But on Mondays and Wednesdays they want to use them to reference the Roman warm period or the LIA. But then given that the proxy data does not agree with deniers claims on either it's hard to see what point it is they are actually trying to make. Deniers tell us that the LIA was a quite cold period and had some solid climatic changes (like the Thames periodically freezing) yet the proxy data show it cooled only ~1c, yet these same deniers tell us the 1c rise we have seen means nothing and is to small to make a difference. The Roman warm period is a similar tale they bleat about grapes in the U.K. as if that is something odd yet the U.K. has in the last few decades developed a quite solid wine industry with grapes grown up as far as Southern Scotland.
As with many denier fables the story changes with the particular tales deniers are pushing on a particular day, and whether that contradicts what they said yesterday or last week seems to not matter to deniers in the least. This is of course made obvious when you press deniers for the sources of these claims and all they can present is the same old blog nonsense.
If we are going to base "the warmest period" on what the data says then Big Gryph is probably right the last decade is the warmest decade in the modern record and the modern record shows as warmer (in it's later half) than the averaged proxy record of the last 2000 years, in the data which (above) goes to 2004 that year is well above those in the averaged proxy record and now in 2013 we have a number of years that where warmer than 2004.
I would say the Medieval Warm Period, based on Mann et al 2008. This is probably surprising to people since that paper was reinforcing the hockey stick. The reason that paper convinces me the Medieval Warm Period was warmer, where other papers and claims did not, is because of the very hockey stick Mann created. The algorithm used in the paper creates hockey sticks out of random data, by comparing proxies to the modern temperature record, and using the ones that match modern warming. Yet despite all that, Mann couldn't create a hockey stick without using an upside down graph, taking a proxy that showed cooling(because of contamination) and interpreting it as one that shows warming, or by using a bristlecone pine proxy which a panel of the National Academy of Science said should not be used.
If he needs to go to such contortions to create a hockey stick, despite an algorithm that is designed to help him, that tells me the underlying data is very much against him.
It's hard to tell, because the further back we go, the less certain our records get.
The 3 candidates, to my knowledge, are now, about 1000 years ago, and about 2000 years ago. But our records for now include direct records for the entire world, while our records for 1000 and 2000 years ago are heavily reliant on proxies, and disproportionately European.
If I had to bet, I think now might be at least a little ahead of any time else in the past 2500 years. But the temperature rise has been so fast that indirect measures, such as glacial mass, haven't quite caught up yet...
It is probably the Roman Optimum 2000 years ago but it is hard to say for certain with all the natural history revisionists that have tried to exaggerate the present. I suspect the MWP was similar to present temperature as well.
Medieval period, when the vikings were in Greenland, the Roman period was nearly as warm too.
I would have to check my time lines, but I beleive that would be the Roman climate Optimum. Go back a bit further and you can include the Halocene Climate Optimum.
The summer of 2013 was pretty hot here ... July was the warmest on record in certain parts of the country.
The last decade
I dunno but this summer in Australia its going to be the hottest summer we have ever had on calender years
Let's open this up to everyone.
