Visitor Essay by Kip Hansen — 4 February 2023
NOTE: I wrote this unique two-part collection almost 5 years in the past now. This reprise has been prompted by a dialog with a colleague who’s solely understanding of Local weather Change or World Warming has been gleaned from NPR/CNN/PBS and Major Stream Media. I assumed to replace this essay to see if I might have the identical opinions right this moment as I did 5 years in the past. Up to date textual content will probably be on this lighter blue colour. Modified or added pictures will probably be clearly labelled.
I’ve usually been requested “Why do you deny local weather change?” I’m all the time stumped by the query. It’s relatively like being requested “Why do you torture harmless animals?” The questioner isn’t merely asking for info, they’re all the time making an accusation — an accusation that they think about very critical and a risk to themselves and others.
The rationale it stumps me is that, as you might have guessed already, I don’t deny local weather change (and I don’t torture harmless animals — nor even responsible ones). And there’s nothing about me or my habits, current or previous, that I’m conscious of, that might lead any affordable particular person to suppose such a factor of me.
I’m totally responsible although of being very skeptical of what’s typically known as the Local weather Consensus — normally mentioned to be represented by the newest stories and coverage suggestions put out by the Intergovernmental Panel on Local weather Change (IPCC) and its supporters; political, ideological and scientific. I suppose it’s this that results in the false accusation of “denying local weather change”.
Be aware: My colleague had been indoctrinated to imagine that the 2 sides of the difficulty consisted of solely two positions: The IPCC Consensus workforce opposing those that suppose World Warming is a hoax.
And there’s the crux of the matter — it’s one thing within the thoughts of the accuser, not any motion of the accused, which results in the false accusation.
MY DENIAL:
I deny that I’m a Local weather Denier, a World Warming denier or another sort of a “denialist”. And I don’t suppose that World Warming is a hoax.
WHY I DON’T DENY:
I don’t deny both of the 2 main claims of the World Warming Motion:
1. World Warming is going on
2. Human exercise causes [some of] it.
Right here’s why I don’t deny #1: World Warming is going on.
There is no such thing as a must replace this part very a lot as it’s long-term historic knowledge – although at finish of part I’ll put in a present World Temperature graphic for completeness.
I’m completely blissful to simply accept that the “world” (the “world local weather”) has warmed because the late 1800s. We all know that the date of 1880/1890 is picked for the place to begin of many of the up to date consensus view plots — purportedly as a result of it represents “the beginning of the trendy industrial period”, this even if even the IPCC doesn’t declare that “CO2 induced world warming” began at that date. Let’s take a more in-depth take a look at Lamb and ”Lamb_modified_by_Jones”:
Be aware: This picture cleaned up a bit. CET is Central England Temperature, which is used as a result of the document is precise measurements steady since mid-17th century.
We all know that Lamb was exhibiting a stylized “schematic” view of Central England temperatures — and Jones 2007 re-does the evaluation with very barely totally different outcomes, then overlays (in blue) the measured Central England by 2007. This graph incorporates the seed of my certainty that “world warming is going on” — which, in un-politicized language could be one thing like: “The Earth’s basic local weather has warmed since a bit earlier than 1700 CE — i.e., for the final 300+ years.” Right here’s Spencer 2007:
And when you favor, right here’s the NOAA model with comparisons of assorted reconstructions :
Be aware: The hyperlink to the file above is now not legitimate. However there’s a related graphic used within the report of the Nationwide Analysis Council’s Committee on Floor Temperature Reconstructions for the Final 2,000 Years beneath:
This graphic is new to this essay.
All of them present cooling to roughly 1650 – 1700 and basic warming since then.
From the place does my skepticism come up then? Nicely, there isn’t any extra — basic warming began about 1650-1700, perhaps a little bit earlier, and has been ongoing. When warming doesn’t begin is 1880/1890 — it begins 100 and fifty to 2 hundred years earlier — earlier than the beginning of the elevated CO2 output of the trendy Industrial Revolution. This makes me very skeptical certainly of the declare that the economic revolution and trendy warming are intrinsically entwined.
And I believe that it’s a good factor that it has warmed since 1700. The Little Ice Age years, up via the 16 and 17 a whole lot, have been exhausting instances for farmers (and thus entire populations) in North America and Europe, as attested to by up to date accounts of crop failures and exhausting winters.
To my data, this level isn’t controversial and even contested. Within the Consensus Worldview, it’s merely over-looked and never talked about. In truth, since the information don’t match the narrative — the narrative that world warming was attributable to the beginning of the Industrial Revolution and its subsequent CO2 emissions — this truth appears to have been down-played or ignored.
Most present temperature graphics:
The above is World Temperature Anomalies since 1880, with the vertical scale set to a selection of 5°C – the vary really useful by U.S. OSHA for workplace temperature consolation.
What does the IPCC say? “Warming of the local weather system is unequivocal.” — IPCC AR5 SPM 1.1
Nicely, I couldn’t agree extra — furthermore, it has been warming since about 1650-1700, 2 hundred years earlier than the Industrial Revolution begins pouring out CO2.
What else does the IPCC say? “ … latest anthropogenic emissions of green-house gases are the best in historical past.” — IPCC AR5 SPM 1
Once more, I don’t disagree:
With out arguing about when “historical past” started, and taking a look at atmospheric CO2 concentrations relatively than emissions, we are able to stipulate that the graph the European Geophysical Union provides us is an “correct sufficient” image of CO2 concentrations during the last thousand years. CO2 stays a shaky 275-290 ppm for 800 years after which begins to point out an increase round 1850, lastly breaking into new territory circa 1880-1890 — the beginning of the trendy Industrial Period. The Wiki provides us the next, once more confirming that CO2 doesn’t start to rise till 1890-1900, lengthy after temperatures start to rise.
It’s merely a incontrovertible fact that atmospheric CO2 focus has been rising since 1880-1890-1900 (shut sufficient for my goal right this moment) and that it’s now greater than it has been in a very long time. Some suppose that this can be a good factor, because it has led to a resurgence in flora on Earth’s floor and some suppose it’s a unhealthy factor.
Atmospheric CO2 has been rising — however is there doubt about this? — “ … latest anthropogenic emissions of green-house gases are the best in historical past.” ?
Whereas it’s not simple to measure atmospheric CO2 concentrations, it has been being carried out for fairly a while….and we have now been capable of guess about human greenhouse-gas emissions and their sources. [These are naturally abject guesses, but we needn’t argue with them on that account — they are our “best guesses”).
The IPCC’s AR5 includes this graphic:
We see that recent emissions are highest, at least in this history, but notice that cumulatively up to 1970 (see the right hand inset bar graph), Forestry and other land use accounts for more than 50% of all CO2 emissions. This surprised even me — I was expecting a pretty big contribution from the clear-cutting and conversion into pasture and farmland of much of Europe and North America east of the Mississippi River — but I had no idea that Forestry and Land Use accounts for >50% all the way to 1970 –and that’s nineteen seventy, not eighteen seventy. By some proxies, global surface temperature had been rising for 300 years by 1970.
Keeping that fact in mind, let’s see what else the IPCC has to say about causes:
IPCC AR5 SPM 1.2 — “Anthropogenic greenhouse gas emissions have increased since the pre-industrial era, driven largely by economic and population growth, and are now higher than ever. This has led to atmospheric concentrations of carbon dioxide, methane and nitrous oxide that are unprecedented in at least the last 800,000 years. Their effects, together with those of other anthropogenic drivers, have been detected throughout the climate system and are extremely likely to have been the dominant cause of the observed warming since the mid-20th century.”
This language is not found in AR6 – the most recent Assessment Report. AR6 Summary for Policy Makers says “It is unequivocal that human influence has warmed the atmosphere, ocean and land. Widespread and rapid changes in the atmosphere, ocean, cryosphere and biosphere have occurred.” AR6 stands by the AR5 statement above without changes.
The IPCC in their synthesis report for policy makers says that human emissions of greenhouse gases and “other anthropogenic drivers,” are “extremely likely to have been the dominant cause of the observed warming since the mid-20th century.”
Well, OK. This is where my Climate Skepticism begins to gain some traction. Dr. Judith Curry, president and founder of Climate Forecast Applications Network, recently offered the following graphic in an essay entitled “Fundamental disagreement about climate change”:
I would have used slightly different points and alternate wordings — but the essence would be the same.
The IPCC Consensus general position is shown on the left — CO2 (and other greenhouse gases) are the primary “forcing” of climate — with changes in CO2 causing changing climate (basically warming) — this warming amplified by feedbacks, like increased water vapor and clouds.
On the right is Dr. Curry’s general view — I share much the same viewpoint. I would have placed place more emphasis this:
Climate is Chaotic: It is composed of highly complex, globally coupled, spatio-temporal chaotic, resonant systems.
So far, I agree with all the facts, but don’t agree with recent CO2 (and other) emissions being “the dominant cause of the observed warming since the mid-20th century.” — I agree neither with the attribution or the effect size.
Today, five years later, I still find myself with the same position: There is no scientific reason to accept the IPCC position and the IPCC offers only that global temperatures have risen (stipulated: the factual matters are not in dispute) and CO2 concentrations have risen (also stipulated).
# # # # #
If you aren’t yet bored to tears, you can find out more on my reasons for that in Part 2, to be published in the next day or so.
The reprise of Part 2 should appear here in about a week.
# # # # #
Author’s Comment Policy:
I have tried to use examples, graphs, that would be generally acceptable to both sides of the Climate Divide, and to avoid controversial minor or fringe sources. I didn’t need to — I am happy with the data presented and that’s Why I Don’t Deny.
I suppose that many readers will disagree with my lack of denial or agree but have different reasons. That is how it should be in a new young field of science like Climate. Feel free to tell all in your comments. I may reply to rational, collegial remarks, questions and requests for clarification.
I am, however, too old to argue. (and five years older now)
The latest IPCC assessment report, AR6, adds nothing that changes my opinions from those of five years ago. There are no new facts that show anything other then the simple “the climate has warmed” and “atmospheric CO2 concentrations have risen” and “are higher than they have been in a long time” – both of which I am happy to agree with. In fact, I think that both are “good things”.
I invite your comments on anything I have written above or on the data presented.
Address comments to “Kip…” if you expect a response.
# # # # #
