To Ant.

Wikipedia.

The Roman Warm Period, is a proposed period of unusually warm weather in Europe and the North Atlantic that ran from approximately 250 BC to AD 400.[1]

• Late Antique Little Ice Age
The Late Antique Little Ice Age was a long-lasting Northern Hemisphere cooling period in the 6th and 7th century AD.

The Medieval Warm Period (MWP) was a time of warm climate in the North Atlantic region that may have been related to other warming events in other regions during that time, including China[1] and other areas, lasting from c. 950 to c. 1250. Other regions were colder, such as the tropical Pacific. Averaged global mean temperatures have been calculated to be similar to early-mid 20th century warming. Possible causes of the Medieval Warm Period include increased solar activity, decreased volcanic activity, and changes to ocean circulation.

• Little Ice Age
The Little Ice Age (LIA) was a period of cooling that occurred after the Medieval Warm Period. Although it was not a true ice age, the term was introduced It has been conventionally defined as a period extending from the 16th to the 19th centuries

Gee willackers, Margaret. I guess there is such as thing as climatic variability, and the globe warms and cools without reference to human induced CO2 levels at all, as well as by solar activity levels. Funny how Manne's flat line graph hockey stick graph completely missed these inconvenient climate variables. No wonder he started his graph in 1000AD, if he had gone back to 1000 BC he would have had to air brush out two or three more climate variations, and even you might have figured out that the climate is cyclical. It warms and cools, Warms and cools. We are just in another warming period. Your own hockey stick graph that you submitted missed them too, and it was almost identical to Manne's

Lego

I have provided references in relation to the Medieval period, remember Frederik Ljungqvist, his graph was tampered with. The Medieval period was warm, but not as warm as the current period. There are a number of references backing that up. Except you do not view the references I provide.

General comments:

Extreme cold conditions in the US this winter is promoted by some to show that climate change is not happening. Yet, in some other countries there have been very warm conditions. Britian has had a very warm February, even including wildfires. Australia has had a very warm February also.

The point is, that we will not know until the end of the year what the aggregate global temperature is. Remember extreme conditions cut both ways.

http://www.carbonbrief.org/media-reaction-uks-record-breaking-winter-heat-in-2019?utm_campaign=RevueCBWeeklyBriefing&utm_medium=email&utm_source=Revue%20newsletter

Oxygen levels in Oceans is dropping, if you do not believe it to be the case, provide data that says otherwise. "... Oxygen levels in some tropical regions have dropped by a startling 40 percent in the last 50 years, some recent studies reveal. Levels have dropped more subtly elsewhere, with an average loss of 2 percent globally."
Note it is not conservative ideology or progressive ideology that determines availability of oxygen in the marine environment.

http://www.scientificamerican.com/article/the-ocean-is-running-out-of-breath-scientists-warn/?utm_campaign=Carbon+Brief+Daily+Briefing&utm_medium=email&utm_source=Revue+newsletter&fbclid=IwAR3SMnBWd1a9dtVAi-wXaeRzooEkPiGcE8FUcK6oPXn2w6lj2_vbPzSy6sM

Fish stocks are disappearing, partly through over fishing and ....
"Ocean warming has led to a 4% global decline in sustainable catches, the greatest amount of fish that can be caught without depleting stocks long-term, according to a study published Thursday in the journal Science."

http://edition.cnn.com/2019/02/28/world/climate-change-fishing-oceans-global-warming-intl/index.html

To Ant.

And I can provide you with climate scientist Dr. Tim Ball's research that the Medieval Warm Period was 2 degrees hotter than it is today. Which side is right? I don't know, and you don't know. But one side or the other is telling porky pies.

You can just keep submitting endless "scientific" reports which supposedly support HIGW, but that means little to me. Because even your side admits that science is being corrupted, with both sides accusing the other of being in the pay of vested interests. So, the real question becomes, just which side is lying, and why?

My contention is that it is your side which is lying. One good reason for that, is that it is the HIGW faction which overwhelmingly has the most to gain by claiming that HIGW is real. The relatively unimportant and poorly funded science of climate research has gone from almost obscurity, to being feted as the Saviours of the World. And it has been lavished with funding to keep the scientists researching. This includes opportunities for lots of adventurous travel to exotic locations, like investigating how global warming is affecting the sex life of the Adele penguins in Antarctica, or affecting the breeding cycles of the red nosed puffer fish in the Great Barrier Reef.

Another, is that HIGW just happens to suite the political and social objectives of the socialist left. So, it is not surprising that HIGW is the most treasured cause of the left wing loony, PC crowd.

Another. Whenever there is a dispute about anything, it is obvious that the side which is uses force, or legal sanctions, to shut the other side up, is the one with something to hide.

Another. The doomsday predictions of the HIGW scientists which was used to frighten the public in order to get the cash flowing, have been proven laughably wrong.

Another. Really smart people are no longer buying it. Coastal real estate prices have not plummeted, alpine prices not soared, and banks and investment houses are still giving credit on purchases of coastal real estate

Lego

On page 1 of comments, Geologist Dan Britt was referenced, he spoke about much climate variability. There is nothing new about that. Except, he stated that instead of beginning to go into an ice age anthropogenic climate change had turned the climate around in the 20th century.

http://www.youtube.com/watch?v=Yze1YAz_LYM

Copy of study by Fredrik Ljungqvist, which goes back to Roman period, the study was published in 2010:

http://agbjarn.blog.is/users/fa/agbjarn/files/ljungquist-temp-reconstruction-2000-years.pdf

Quote:

"Since AD 1990, though, av- erage temperatures in the extra-tropical Northern Hemisphere exceed those of any other warm dec- ades the last two millennia, even the peak of the Medieval Warm Period, if we look at the instru- mental temperature data spliced to the proxy re- construction." It is the Fredrik Ljungqvist study that has been tampered with by deniers. Temperature has continued to rise beyond the cut off point of Ljungqvist's study.

A further more recent study ... "The study, published Thursday in the journal Science, confirms the now famous “hockey stick” graph that Michael Mann published more than a decade ago. That study showed a sharp upward temperature trend over the past century after more than a thousand years of relatively flat temperatures."
And:
"But the new report extends that research back much further, using evidence from the seafloor and from lake sediments to gauge past temperatures, not the tree rings previous researchers have used. “What’s striking,” said lead author Shaun Marcott of Oregon State University in an interview, “is that the records we use are completely independent, and produce the same result.”But the new report extends that research back much further, using evidence from the seafloor and from lake sediments to gauge past temperatures, not the tree rings previous researchers have used. “What’s striking,” said lead author Shaun Marcott of Oregon State University in an interview, “is that the records we use are completely independent, and produce the same result.”"

http://www.climatecentral.org/news/climate-to-warm-beyond-levels-seen-for-at-least-11300-years-15701

You are like a cracked record, Ant. Instead of supporting your case with a reasoned argument, you just drag out some more "science studies" to support your view, and direct me to hot button links. Again, and again, and again. It sure is easier than using your nut to think up an intelligent reply to my premises. I could do the same thing to you, but then the whole debate just reduces to "'Tis, 'tisn't, 'tis, 'tisn't't".

Both sides are accusing the other of scientific fraud. Tim Ball says that the Medieval Warm Period was 2 degrees warmer than today, and your boy says that today's temperatures exceed any warm period in the last two thousand years. Some reports say that the globe is still warming, and others say that we have not experienced any warming for twenty years, instead we are starting to cool.

The crucial question you keep dodging, and dodging, and dodging, is which side is telling the truth? Which side has the greater credibility?

Based upon the latest "explanation" for why climate catastrophe has still not met the civilisation destroying predictions of the HIGW alarmists, your boy is now claiming that we are going into an ice age, and only global warming is keeping the temperature relatively constant. That explanation is at least credible, because just like the charge that humans are affecting climate, it can't be proven. But who needs proof when you are telling left wing people what they want to hear?

But from my side of the fence, if the globe is cooling, then the deniers were right all along. What we have experienced in this particular warming period is simply natural climate variability. And your boy's "explanation" about how HIGW global warming is offsetting natural global cooling, seems to indicate that your boy is aware that temperatures are indeed cooling, as the recent snow storms blanketing the USA seem to show. And the alarmists have no idea how they are going to be able to keep selling their nice little earner fraud to the ever more sceptical public if that keeps happening.

Lego

You have no idea how science operates, I know you won't take notice of what I write, you are trying to mix your ideology with science. Science does not operate on opinions or ideology, it must be replicatible. You have not produced a sterrick of real evidence to support your views.
The references to science of the 1970s was to display how the science was displaying concern about anthropogenic climate change. There was also a reference to a New Zealand newspaper article from1912 that epressed concern about the use of coal. Those were periods before denier groups such as Heartlands began pushing pseudo science to protect the profits of fossil fuel corporations.

I have shown how science gets warped by interpretation by Heartlands and other Agencies. We are now getting to the pointy end of anthropogenic climate change. I wrote about Jerry Taylor who became aware that Heartlands had been feeding him pseudo science. His role had been to con people while working for Heartlands.
I have displayed how the work of Hansen, Alley and Ljungqvist was fraudulently changed to suit denier points of view.

I provide references and quotes from those references to display where you are so wrong. Your comprehension of nuanced information is poor. You write about climate science, but have no idea of conventions.

I'm still waiting a response to my question ... what has happened to the denier datum year of 1998?

Remember, references provided stated that we are have reached 1C over pre-Industrial times. 1C ...over ... pre-Industrial ...times.