[editor’s note. there was a layout issue when published a few hours previously. now resolved]
I often get asked this question on social media, so I decided to provide the answer as a simple primer.
1. The Basics: Climate Does Change
First, let’s be clear — climate change is real in the literal sense. The Earth’s climate has been changing for billions of years. We have geological records showing periods that were much warmer (like the Eocene, with crocodiles in the Arctic), and much colder (like the Ice Ages that covered North America in glaciers).
Even more recently, we have the Holocene Climate Optimum, significantly warmer than present day:

So, yes — the climate changes, and it always has. The debate isn’t about whether it changes, but why, how fast, and how much humans are influencing it today. The debate is also about how accurately we are able to detect temperature change, plus the overreliance on climate models to predict the future rather than actual data.
2. What the “Consensus” Says — and Where It Falls Short
The mainstream position (IPCC, NOAA, NASA, etc.) holds that recent warming — roughly 1.1°C since the late 1800s — is largely due to increased CO₂ from human activity, mainly fossil fuels.
But here’s the rub: this view is heavily dependent on climate models, which are notoriously uncertain. As someone with a meteorology background, I can tell you models struggle with cloud feedbacks, ocean cycles, solar variability, and regional forecasts — all of which are crucial to understanding climate.
When models are run backward, they often fail to replicate past climate variability accurately — like the Medieval Warm Period or the Little Ice Age — unless they’re tuned heavily. That calls into question their reliability for long-term projections.
3. Natural Variability: The Elephant in the Room
A lot of warming in the 20th century happened before CO₂ rose sharply post-WWII. For example:

- The warming from 1910 to 1940 occurred with much lower CO₂ levels.
- Then there was a cooling trend from the 1940s to 1970s, despite rising CO₂ emissions during that time period.
Clearly, natural factors — like solar cycles, ocean oscillations (PDO, AMO), volcanic activity, and cloud dynamics — are still in play and possibly underestimated in mainstream assessments.
4. The CO₂ Connection: Overstated?
CO₂ is a greenhouse gas, no question. But its effect on temperature is logarithmic — meaning, the more CO₂ you add, the less warming you get per unit. The first 100 ppm has the biggest impact, and we’re well past that as seen in the figure below.

Moreover, satellite data from UAH and RSS shows a slower warming trend than surface datasets like HadCRUT or GISS. That discrepancy raises questions about data adjustments, urban heat island effects, and instrument biases.
5. Are We in a Crisis?
Even if we accept that humans are influencing climate, the notion that we’re in an “existential crisis” is unproven. Extreme weather trends (hurricanes, tornadoes, droughts) don’t show clear worsening patterns once you account for improved detection and population growth in vulnerable areas such as coastal developments.
The Intergovernmental Panel on Climate Change (IPCC) agrees, suggesting a “low confidence” in many current and future weather events being affected by climate change. The “existential crisis” view is heavily dependent on climate model projections, which are notoriously uncertain and refuted by data.
Sea level is rising — but at a slow, linear pace of about 3 mm/year. That’s about 12 inches per century, similar to what’s been observed since before industrial CO₂ emissions.
Bottom Line
Yes, the climate is changing. It always has. The idea that global climate must be unchanging is simply wrongheaded. The real issue is how much of today’s change is due to human activity, how reliable our predictions are, and whether proposed policy responses are justified — or likely to do more harm than good.
At Watts Up With That, we’ve been pointing out for years that this issue is riddled with confirmation bias, model overconfidence, and selective reporting. There is no justification for shutting down economies or reshaping civilization based on the incomplete science of climate change.
So yes, climate change is real, but no, it’s not a crisis.
Since nobody can define Climate … it’s impossible to define Climate Change … What is the Climate right now ? Crickets … Nobody can say what it is right now So how can anyone claim it’s changing …
it’s always been a power grab … treat it as such and stop trying to use science to debate it … and
Don’t give me the nonsensical 30 year average or change of something… temp rain sea level etc etc etc … none of those are Climate… so what if they change ? With the corrupted data NOBODY can possibly determine what is changing or by how much… as I say it’s a waste of time …
Don’t allow the cultists to define the playing field … they are pigs in the mud … to attempt to wrestle with them will turn you into just another muddy pig …
Actually it is not complicated. CO2 in the atmosphere is like any other chemical and subject to saturation limits. The first amount of CO2 raises the world temperature the most. The second amount of CO2, less rise. The third amount of CO2, very little. The fourth amount of CO2, almost immeasurable.
The so-called climate scientists all think that the amount of CO2 in the atmostphere affects the world temperature uniformly. The fourth amount of CO2 on the atmosphere has the same effect as the first amount of CO2. That is wrong.
The IPCC uses “low confidence” to mean about a 20% chance, ie, about 4 times more likely to be wrong than right. To my simple mind, those words are highly misleading and probably deliberately so. Something like “very unlikely” or “probably wrong” would be more realistic.
This is incorrect. Here is the IPCC AR6 probability terminology table.
99-100%: virtually certain
95-100%: extremely likely
90-100%: very likely
66-100%: likely
50-100%: more likely than not
33-66%: about as likely as not
0-33%: unlikely
0-10%: very unlikely
0-5%: extremely unlikely0-1%: exceptionally unlikely
There are 5 confidence qualifies that are not to be interpreted as probabilities of likelihood, but instead as an assessment of the quantity and quality of evidence. These levels are very low, low, medium, high, and very high.
“low confidence” does not mean a 20% chance or 4 times more likely to be wrong than right.
Absolutely meaningless gibberish from the IPCC…
… based on fake models, fake attributions and fake surface data.
At least the IPCC stated
100% impossible. No ifs, buts, or maybes.
Does anything else matter?
Easy, stomach, easy….
The only comment which is required: https://tamino.wordpress.com/2025/04/07/global-temperature-can-anthony-watts-sucker-you/ Apart from to ask – Where does the “Marcott” graph in section 1 come from?
I love the closure.
I am open to suggestions regarding how to counter this kind of nonsense.
Seems he is capable of publishing his own nonsense but incapable of justifying the counter point.
It is from panel I of Figure 2 in Marcott et al (2013), screenshot attached to the end of this post.
From the caption for “Fig. 2” :
Compare the (left-hand) scale for the purple “90 to 30N” line with what you call the ATL graph, reproduced here for convenience :
.
NB : I agree with you (and “tamino”) that only preceding the graph with
is problematical, as the natural inference for readers will be to assume it shows a “global mean temperature” reconstruction when it doesn’t.