Follow-up questions… A denier here listed the following “facts” as the reason why he doubts anthropogenic climate change. What do you think of his “facts”?
<<<Here are some facts you can't dispute. (A) The climate varies naturally. (B) We have generally been warming for a few hundred years. (C) The recent (last 100 years) of warming isn't particularly unusual or alarming. (D) It cooled from 1940s to 1970 in spite of increased CO2. (E) The theory that CO2 is suddenly driving climate variation is hardly a theory at all. It is more like a guess…>>>
I have these additional thoughts and questions:
(A) OK, that’s a no-brainer. Was this ever in doubt?
(B) Has the rate and pace of warming over the past few hundred years always been the same? The climate doesn’t change for without reason; do we have any reasonable hope of determining the different forcings that contributed to climate change over the past few hundred years? If so, what were these forcings at work?
(C) When was the last time the global temperature change 0.8°C/century? What could have forced this climate change?
(D) Again, what different forcings were at work from the 1940s to 1970s? Did the global temperature really decline during this period?
(E) Why would CO2 forcings “suddenly” pop into existence? Hasn’t CO2 forcings always been in existence?
Update:@bravozulu, I'm not trying to disprove his "facts". I'm just trying to gather more information.
Answers & Comments
Verified answer
(A) Duh.
(B) Seems true. The rate and consistency of temperature increase has increased. Up until the early part of the 20th century, this could be explained by solar activity. After then, it can't.
http://rspa.royalsocietypublishing.org/content/464...
http://www.iop.org/EJ/abstract/1748-9326/4/1/01400...
http://www.geo.umass.edu/faculty/bradley/lean1995....
(C) The Younger Dryas and 8.2ky events were quicker, at least in some regions. They were caused by cutting off the Gulf Stream, which caused ice to spread which then acted like a giant mirror.
(D) It cooled in the 1940s, and then wobbled at a roughly constant T before going up after the 70s.
http://data.giss.nasa.gov/gistemp/graphs/Fig.A2.lr...
Climate models expect this, based on emissions of CO2 and aerosols. In short, non-CO2 pollution acted as a 'sunshade' causing 'global dimming' which partially canceled out CO2's warming. Thanks to clean air legislation in Europe & the US & its short atmospheric lifetime, it couldn't keep up with increased greenhouse effect (although some evidence suggests aerosols are going up again thanks to Chinese industrialisation)
This graph, based on Meehl et al 2004, should help explain it!:
http://old.avenirclimat.info/public/Images/graph/C...
(E) CO2 forcing has always been around. There are times where it has helped to drive temperature. Like the Paleocene-Eocene Thermal Maximum, Proterozoic & Devonian. Recently (~600kyrs or so) it has tended to act as a feedback, because nothing has been able to change it drastically before temperature changes. Temperature has changed because of changes in Earth's orbit, and then CO2 bubbles out of the ocean over the following centuries, causing more warming.
Since it has acted as a feedback recently, many skeptics will say that it _can't_ act as a forcing, or it doesn't exist. This requires ignoring the numbers which show orbital forcing can't account for the temperature changes. You also have to ignore some other inconvenient truths (like quantum mechanics) to believe CO2 can't drive temperature.
solid to verify deniers shown for what they are actually. Watts has over the years published an excellent number of incorrect and fake concepts, yet then this is the reason he exists interior the 1st place. Deniers are consistently speaking approximately fraud and information manipulation yet it rather is easily their area this is doing this, and not o.k. at that. this is with regard to the 4th or 5th a sort of I easily have seen according to infomation coming from Watts.
B) We don't have enough data to determine past warm-ups from past mini ice ages.
C) Most likely when we exited the Medieval Warming Period so I would say from 1250 to 1350 when Greenland ended up being abandoned.
D) Most AGW people ignore this period of cooling.
E) All of the information has shown that past warming has caused increases in CO2 not the other way around.
Also, from what I understand, water vapor has doubled in the atmosphere and since it makes up 95% of all greenhouse gases wouldn't this be the smoking gun?
Your questions and your answers are like nails on a chalk board. I'm not sure if it's the poor English, the redundancy of adverbs or the blatant attempt to become one of the tribe but I can't read anything you write with out begging for a question from Paul.
A. Whoopdy-do
B. Rate and pace are the same thing.
C. Well, that ones a bit difficult to tell with unreliable proxy data, but let's just rely on what we have anyways huh. No need to get all technical here.
D. The same that are at work now.
E. See answer D above.
If global warming is happening as you say, why has the world been COOLING for the past few years? Yeah, my link goes against GISS and other liars in the "(junk)scientific community" but if they can't tell the truth they need to be exposed for the useless entities they are.
A) Duh.
B) Too vague to even comment on.
C) Compared to what? It's unusual and alarming when compared to the past 8,000 years.
D) It barely cooled over that period, and so what? Strawman alert.
E) Somebody needs to look up the definition of a scientific theory.
As to question (C) - Medieval Warm Period. I don't think anyone disputes this.
You can't rationally dispute any of the obvious facts except with political unscientific propaganda. Your fantasy that the facts mentioned don't utterly destroy the premise of significant warming is just simply denial. Relying on data from known liars is further denial. You are obviously in total denial and it is past boring to hear the term denier coming from such a total denier of reality.
Climate change denial is along the lines of evolution denial. In scientific circles, it has been accepted as mainstream fact for years, but thanks to your capitalistic society and big corporations and their PR companies, it is being denied all the time in mainstream media, or at least being doubted.
The polar ice caps are melting, that's a fact.
The greenhouse gases effect is a fact.
Accelerated global warming, is a fact.
CO2 is not only a green house gas. Lots of it is being dissolved in the oceans, increasing their acidity. Of course, carbonic acid is a very weak acid, but this minute change in pH is affecting many of the diverse wild life in the oceans.
Global warming is real, but quite beneficial. If we all work hard we can warm up the planet and I won' t have to shovel snow. I hate doing that:
http://www.greenpees.com/