Answers to some climate change objections

Planet Earth on the stove
Planet Earth on the stove

Despite the evidence that has been amassed over recent decades that shows conclusively that man-made climate change is a reality, there are still people who seek to deny that this is so. However, their arguments are specious as will be explained below. Here are six such arguments that are regularly put forward but which cannot be accepted, for the reasons given.

1. Climate change is not caused by humans

It is certainly true that the average temperature of Planet Earth can rise or fall without human intervention, but this is simply not the whole story when it comes to the current rise in global temperature.

There are many factors that must be taken into account when assessing why the temperature is rising, but those that can be deemed “natural” are insufficient to produce the observed rise. There is no logical alternative to the conclusion that human activity must be a major cause.

This activity relates to the action of certain gases in the atmosphere that trap the sun’s rays and cause the land and sea to get warmer. The protective layer of the atmosphere is what makes life on Earth possible at all, because without these “greenhouse gases” the surface would be 30⁰C cooler than it is. However, if the temperature gets too high the consequences could be disastrous for most lifeforms on the planet.

The main greenhouse gases are water vapour, methane and carbon dioxide. Human activity increases the amounts of these gases in the atmosphere, which in turn leads to increased warming. There are no natural processes that could possibly cause these amounts to rise to the levels that are currently observed.

Global temperature rise 1880-2009, matched to levels of atmospheric carbon dioxide
Global temperature rise 1880-2009, matched to levels of atmospheric carbon dioxide

2. Carbon dioxide is not responsible for global warming

It can be shown experimentally that CO₂ (carbon dioxide) is a very efficient molecule in terms of trapping heat, so it has a disproportionate effect on global warming despite being relatively rare in terms of its presence in the atmosphere when compared with other gases.

It is true that water vapour is more significant than carbon dioxide in terms of its direct effect on atmospheric temperature, because it condenses to form clouds that may warm or cool depending on their type and location. However, any warming due to carbon dioxide will lead to increased evaporation and therefore a more humid atmosphere.

Carbon dioxide levels have risen from pre-industrialisation levels of around 280 ppm (parts per million) to 380 ppm, due partly to the burning of fossil fuels but also due to other causes such as deforestation (forests absorb CO₂ that would otherwise remain in the atmosphere).

CO₂ is both directly and indirectly implicated in the increase in global warming noted since mankind starting burning fossil fuels on an industrial scale.

Sea ice in the Arctic, 1984 and 2012
Sea ice in the Arctic, 1984 and 2012

3. The rise in CO₂ levels came after global warming and not before

The reason for this statement is that observed levels of CO₂ in ice cores show that these rose after the onset of the Ice Ages, which were caused by fluctuations in Earth’s orbit around the Sun. From this, it is argued that CO₂ cannot be implicated in causing global warming.

The answer to this is that greenhouse gases are released from both land and oceans as they warm, which they would have done as the Ice Ages reached their end. These gases would then have caused further warming in a form of “positive feedback”.

However, these were purely natural processes that have no relation to what is happening in the modern world of human activity. It can be shown, from chemical analysis, that most of the CO₂ produced in recent years is the result of fossil fuel burning and has not derived from natural sources.

In other words, it is not possible to extrapolate modern conditions from relying on ancient ice core data.

Earth's energy budget
Earth's energy budget

4. The theory is not supported by temperature observations

The reasoning behind this claim is that readings taken during the early 1990s by instruments carried by satellites and weather balloons, of temperatures in the lower atmosphere, did not accord with what was observed at the surface. There was therefore a mismatch between the climate models that were based on the atmospheric data and what was actually experienced at ground level. In other words, the scientists had got it all hopelessly wrong and could not be trusted to tell the truth. From this arose all sorts of accusations about how climate scientists were part of a conspiracy to defraud the world’s population into taking expensive measures to prevent a catastrophe that would never happen.

However, the truth was soon appreciated when it was realised that the data had been wrongly gathered and/or interpreted. There were problems with some of these early measurements caused by, for example, satellites changing their orbit and giving inconsistent readings, and by simple mathematical errors. Once these discrepancies were sorted out, data from these sources has proved to be highly reliable.

It has also been objected that temperatures in the upper atmosphere – the stratosphere – show cooling rather than warming. However, this is due to ozone depletion, which has a knock-on effect on other parts of the atmosphere but which is quite independent of any effect caused by greenhouse gases.

The Greenhouse Effect
The Greenhouse Effect

5. The computer models of global warming are unreliable for predicting future climate change

Climate change deniers seem to expect scientists to know exactly what will happen in the future and regard any adjustment in computer models to be an admission that scientists are unable to make accurate forecasts.

However, it has to be appreciated that many factors are at play in terms of climate change, and all a model can do is take these factors on board, based on past and present conditions, and suggest where the trends will take us in future.

Although it is possible to include past data and refine the models as more such data is obtained, there will always be uncertainties in terms of what will happen in future. For example, population growth is a known factor in terms of the past, but what of the future? It is only possible to make assumptions that may not prove to wholly accurate.

A model can only predict the future in terms of “if X and Y happen, then the result will be Z”, but there can be no certainty that X and Y will actually happen.

The important thing about these models is that they can give clear indications of general trends. The degree to which the climate will change in future will depend on the extent to which certain factors come into play, but this uncertainty does not invalidate these trend indications.

Satellite view of two tropical storms
Satellite view of two tropical storms

6. The negative effects of climate change have been overstated

It is often objected that climate scientists are unduly pessimistic about the effect that a modest rise in global temperatures will have. Even if it is accepted that average global temperatures will rise by 2-3⁰C during the current century, will that really make a heap of difference?

The answer, in short, is – yes, it will. Such a rise is unprecedented during the past 10,000 years, and for it to happen in such a relatively short period of time could have very serious consequences both for people and ecosystems.

There might indeed be some benefits for some parts of the world from temperatures being generally higher, such as increased growing seasons in northern latitudes coupled with the fertilising effect on plants of increased atmospheric carbon dioxide.

However, it would not be long before the negatives started to outweigh the positives. Warmer oceans will generate more severe weather events such as tropical storms, not to mention generally increased rainfall caused by greater evaporation, leading to more incidences of flooding.

Some inhabited parts of the world rely on snowmelt for their water supply, but if the mountains receive their precipitation as liquid rain – which runs off quickly into the sea – as opposed to snow that melts gradually and fills reservoirs, then water supply will be a real problem. This is something that places such as California on the west coast of the United States are already facing.

Rising sea levels, due both to melting icecaps and the overall expansion of ocean water, will have a disproportionate effect on the world’s low-lying countries and islands, many of which are in regions where the population is generally under-developed and therefore least able to adapt.

The negative effects of climate change have not, therefore, been overstated.

More by this Author


Comments 19 comments

HSchneider 17 months ago from Parsippany, New Jersey

Excellent Hub and refutation of the climate change deniers. None of their arguments are based in fact or science. They simply want to preserved the status quo which is destroying damaging the planet and threatening the lives of our children and grandchildren.


jackclee lm profile image

jackclee lm 14 months ago from Yorktown NY

I have a few other objections but the main one being solar activity. Can you address the fact that our sun is going into a quiet period. The sunspot cycle is weak recently and scientist have little explanation.


nicomp profile image

nicomp 12 months ago from Ohio, USA

We're fine. There's no anthropogenic climate change. Global Warming is a massive political hoax perpetrated by liberal governments for the purpose of controlling the masses.


The Indexer profile image

The Indexer 12 months ago from UK Author

It amazes me how people can be shown all the evidence there is, compiled over many years by thousands of highly qualified experts from all over the world, and then say that the evidence doesn't exist. Unbelievable! It's no wonder there are still people around who think that the Earth is flat!


nicomp profile image

nicomp 12 months ago from Ohio, USA

It amazes me that people still don't understand science. And people still refer to discredited studies by discredited scientists. If I asked you about Michael Mann's "Hockey Stick" could you explain the controversy? Doubtful.

We need more STEM education in our schools because people still think science is performed by consensus. As a sentient human with 2 science degrees and grinding through a third , I have a pretty good grasp on the Scientific Method but sadly I am one of the few.

It does not matter one whit how many scientists agree on something. We don't arrive at a conclusion by voting on it. We don't elect theories.

It also makes me sad that people don't understand computer simulations and how they are manipulated, but no one will read the work of McIntyre & McKittrick to learn how Michael Mann was discredited. It makes me sad that people don't understand how one single solitary bristlecone pine tree became the basis for an entire body of proof for 'global warming.'


The Indexer profile image

The Indexer 12 months ago from UK Author

McIntyre and McKittrick? Two so-called experts whose work has long since been discredited! They are both very closely connected with the fossil fuel industry, so can hardly be relied upon as disinterested commentators.

Yes I do know something about the hockey stick controversy, and that McIntyre and McKittrick think they have discredited Michael Mann's claims. However, a closer examination of what they have said shows that they have done nothing of the sort.


jackclee lm profile image

jackclee lm 12 months ago from Yorktown NY

What percent of human influence has on climate change in your opinion? That is the main question. It is not whether some are deniers of climate change. The better term is either a skeptic or a doubter. Anyone who does not buy into the claim of human caused climate change and the drastic effects on our environment is labeled a denier. There seems to be no room for debate. I leave you with one thought and question. What percent do you think the sun play in climate change? And do you think man has any control over the sun's activities?


The Indexer profile image

The Indexer 12 months ago from UK Author

There certainly are deniers as well as doubters! It is not possible to put exact figures on specific influences on climate, because it is all extremely complex and dynamic. However, the fact remains that it is not possible to make sense of the observed data - which is measurable - without taking human factors into account. The latter are certainly not a trivial part of the picture - solar variation cannot possibly be the main cause of what is observed.


jackclee lm profile image

jackclee lm 12 months ago from Yorktown NY

Indexer, how sure are you and are you willing to put some skin in the game? My problem with the climate scinentists is they make extreme claims and they are guessing, and exagerating the effects. They are asking us to trust them when the climate system is very complex as you've admitted. The cost of some proposals are not trivial. The poor and the third world citizens will bear much of the burden. The scientists have little to loose if they are wrong. If they would take responsibility for their predictions, I would be more inclined to believe them. What are you willing to do if climate change turns out to be natural variation?


nicomp profile image

nicomp 12 months ago from Ohio, USA

McIntyre and McKittrick were not discredited.


The Indexer profile image

The Indexer 12 months ago from UK Author

They certainly were by many of the real experts in the field.

To answer Jacklee - let us suppose that the degree of certainty that climate change catastrophe is 25% - ie this is the probability that the effects of rising sea levels, etc, will cause major problems within 50 years. Would you be willing to take a chance on this, or would you take steps to mitigate that effect while you can? (I'm not saying that 25% is the figure, merely offering this as a point of argument)

You might think that a 75% chance that all will be well is worth taking. OK - suppose I said that the chance of the plane you are boarding will crash is 25%. Will you still get on board?

What climate scientists do is make models based on observations of present and past conditions and project them into the future. OK - there have been exaggerations, and these are unfortunate because people then swing to the opposite extreme and deny that anything terrible will happen at all. However, the projections are worth taking seriously because they are based on real science and not guesswork.

Real scientists always consider every possibility that could invalidate their claims. They have looked at whether non-human causes could explain their observations, and have come to the reluctant conclusion that this is not possible. Unless you allow for anthropomorphic causes the figures simply don't add up.

Yes, the solutions could be expensive, but nothing like as expensive as waiting until the effects become so obvious that even the sceptics can't ignore the evidence. It is the poorest people in the world who will be the first to suffer from the adverse effects of climate change because they will not be able to adapt to change as easily as those in richer nations.


nicomp profile image

nicomp 12 months ago from Ohio, USA

"They certainly were by many of the real experts in the field."

No, they weren't. They are experts in their field.


nicomp profile image

nicomp 12 months ago from Ohio, USA

"To answer Jacklee - let us suppose that the degree of certainty that climate change catastrophe is 25% - ie this is the probability that the effects of rising sea levels, etc, will cause major problems within 50 years. Would you be willing to take a chance on this, or would you take steps to mitigate that effect while you can? (I'm not saying that 25% is the figure, merely offering this as a point of argument)"

Now I know you don't understand science or math. You pull numbers out of thin air, assert that they seem reasonable, and base your argument on them.


jackclee lm profile image

jackclee lm 12 months ago from Yorktown NY

Nicomp, indexer, your analogy with the airplane is false. If the probability of crash is 25%, we can choose not to fly and that would be the end of it. With climate change, a better analogy may be living in Kansas with the annual possibility of tornados. We don't have a good handle on predicting the frequency or location where a tornado will land. In either case, we can't control it. What we can do is do the sensible thing of building a shelter. When it comes, we go to the shelter and wait it out. We don't tell everyone to change their live style or build a wall around their home to protect it against a natural event that may or may not strike. The cost/benefit analysis is what is missing in the proposed solution to climate change.

Nicomp, with regard to your comment about math, I know math too well and I know more about how these computer models work. You can tinker with a small variable and change the outcome over a long period. That's been the problem with their long range projections. They rely too much on incomplete models and when the results don't fit, they just tinker with the data.


nicomp profile image

nicomp 12 months ago from Ohio, USA

"Nicomp, indexer, your analogy with the airplane is false."

Whoa jackclee lm, I didn't make the analogy. I only pointed out the duplicitous nature of the analogy.

"Nicomp, with regard to your comment about math, I know math too well"

Whoa again jackclee lm -- I was observing that The Indexer is deficient in math.

-- nicomp


The Indexer profile image

The Indexer 12 months ago from UK Author

I am working on the basis of logic, not maths. I pose a logical conundrum - if you accept proposition A, do you accept proposition B?

Would you board a plane with a 25% chance it will crash is a fair question. Would you board it if the chance was 10%, or 5% is also a fair question. In fact, the chance of boarding a plane and dying in a crash is extremely small.

However, the chance that anthropomorphic global warming will cause massive problems for humanity at some point in the future is far from miniscule, and figures of 25% are often mentioned. Some researchers would put the figure much higher.


jackclee lm profile image

jackclee lm 12 months ago from Yorktown NY

Nicomp, sorry for the misunderstanding. Sometimes, it is hard to separate the responses from the commenter. One of my suggestion on improving Hubpages is to have a thread in the comments so a separate dialog can be established.


jackclee lm profile image

jackclee lm 12 months ago from Yorktown NY

Indexer, let me continue with your logic and expand on it. Suppose you are flying on a plane and it't flight path takes you over a combat zone. The safety of the plane is good but the chance of being shot down is 25%. Will that change your decision to fly or not? How can you mitigate the threat?

That is the better analogy with climate change. We have identified a possible problem. Human contribution is one of many causes and some are natural such as sun activity or volcanos or astroids... You can only mitigate the human contribution at great cost. You have no control over the other factors. On top of that, some of what you can do will only have a small impact if at all. What do you do?

The debate over climate change comes down to what percent of the climate is due to human contribution. If it is high, then I would expect the science to reflect it in their projections and the reality to match with what they predict. The fact that that did not come to fruition after 25 years of warning gives me pause and doubt. Why is that so hard for some to comprehend?


nicomp profile image

nicomp 12 months ago from Ohio, USA

"That is the better analogy with climate change. We have identified a possible problem. "

No, we haven't. That's a Straw Man argument.

"Human contribution is one of many causes and some are natural such as sun activity or volcanos or astroids."

No, it isn't. Another Straw Man argument.

"The debate over climate change comes down to what percent of the climate is due to human contribution."

No, you and other folks attempt to frame a debate in those terms. There is no debate.

"The fact that that did not come to fruition after 25 years of warning gives me pause and doubt."

Cherry picking. There have been more than 25 years of warning for global cooling.

"Why is that so hard for some to comprehend?"

I agree. So many people worship the Earth: I don't get it. So many people need a villain.

    Sign in or sign up and post using a HubPages Network account.

    0 of 8192 characters used
    Post Comment

    No HTML is allowed in comments, but URLs will be hyperlinked. Comments are not for promoting your articles or other sites.


    Click to Rate This Article
    working