Where does the heat come from? Can science explain how the heat was stored and released in summer? All due to GHG gases?
The Sun, exacerbated by climate change. Additional greenhouse gases in the atmosphere are trapping more solar radiation, which causes global warming. Yes.
FYI “In Domesday Book (1085) 38 vineyards were recorded in England besides those of the king. The wine was considered almost equal with the French wine both in quantity and quality as far north as Gloucestershire and the Ledbury area of Herefordshire where the soil is said to resemble that of the Rhine and Moselle wine districts. The London basin, the Medway valley and the Isle of Ely were also favoured districts. The northernmost vineyards were near York [northern England] but the most favoured country was from Northants and the Fenland southwards. This implies summer temperatures perhaps 1 to 2°C higher than today, general freedom from May frosts (particularly suggested by the exposure to the north of several low-lying vineyard sites, e.g. at Tewkesbury, in the Fens and at Teynham, Kent) and mostly good Septembers.” https://notrickszone.com/2018/04/02...rown-at-latitudes-where-polar-bears-now-roam/
Ah yes, another old chestnut from the Climate Change Deniers' Playbook. Please Register or Log in to view the hidden image! This relates to the "Medieval Warm Period", a phenomenon specific to N Europe alone, as opposed to a global effect, and which has known causes. QUOTE One of the most often cited arguments of those skeptical of global warming is that the Medieval Warm Period (800-1400 AD) was as warm as or warmer than today. Using this as proof to say that we cannot be causing current warming is a faulty notion based upon rhetoric rather than science. So what are the holes in this line of thinking? Firstly, evidence suggests that the Medieval Warm Period may have been warmer than today in many parts of the globe such as in the North Atlantic. This warming thereby allowed Vikings to travel further north than had been previously possible because of reductions in sea ice and land ice in the Arctic. However, evidence also suggests that some places were very much cooler than today including the tropical pacific. All in all, when the warm places are averaged out with the cool places, it becomes clear that the overall warmth was likely similar to early to mid 20th century warming. Since that early century warming, temperatures have risen well-beyond those achieved during the Medieval Warm Period across most of the globe. The National Academy of Sciences Report on Climate Reconstructions in 2006 found it plausible that current temperatures are hotter than during the Medieval Warm Period. Further evidence obtained since 2006 suggests that even in the Northern Hemisphere where the Medieval Warm Period was the most visible, temperatures are now beyond those experienced during Medieval times (Figure 1). This was also confirmed by a major paper from 78 scientists representing 60 scientific institutions around the world in 2013. Secondly, the Medieval Warm Period has known causes which explain both the scale of the warmth and the pattern. It has now become clear to scientists that the Medieval Warm Period occurred during a time which had higher than average solar radiation and less volcanic activity (both resulting in warming). New evidence is also suggesting that changes in ocean circulation patterns played a very important role in bringing warmer seawater into the North Atlantic. This explains much of the extraordinary warmth in that region. These causes of warming contrast significantly with today's warming, which we know cannot be caused by the same mechanisms. UNQUOTE From: https://skepticalscience.com/medieval-warm-period.htm
Another good explanation from RealClimate: "Claims that global average temperatures during Medieval times were warmer than present-day are based on a number of false premises - namely that a) confuse past evidence of drought/precipitation with temperature evidence, b) fail to disinguish regional from global-scale temperature variations, and c) use the entire “20th century” to describe “modern” conditions. These claims fail to differentiate between relatively cool early 20th century conditions and the anomalously warm late 20th century conditions."
most likely a cumulative effect and solar variation (it was warmer during the holocene climate optimum, and during the medieval warm period-----and many other periods) Please Register or Log in to view the hidden image! see: https://iowaclimate.org/2018/08/19/the-holocene-climate-optimum/
"Claims that global average temperatures during Medieval times were warmer than present-day are based on a number of false premises - namely that a) confuse past evidence of drought/precipitation with temperature evidence, b) fail to disinguish regional from global-scale temperature variations, and c) use the entire “20th century” to describe “modern” conditions. These claims fail to differentiate between relatively cool early 20th century conditions and the anomalously warm late 20th century conditions."
Why the artic iceberg are melting away? Antarctic also melting? How to stop it? I read that polar bears and penguins are threatened of their survivals.
I do not think you can dismiss the medieval warming that easily. It is disturbing that the high temperatures are occurring when earth is the farthest from the sun. There is also the issue of changes in the core activity. What we do know is that co2 levels have never been higher and that is something that can be addressed.
You seem to be rather opinionated on this subject. Have you considered the very real possibility that your assumptions are, most likely, wrong? .................................. here is your missing 'h'
These are some links that may be useful for such discussions: https://www.climaterealityproject.o...ive-tips-how-talk-climate-deniers-your-family https://www.nytimes.com/2020/01/02/opinion/climate-change-deniers.html https://www.bbc.com/news/blogs-trending-61844299 https://grist.org/climate/skeptics-2/