(about climate change)
Firstly the title of this page is not mine, it came from a series of posts at skepticalscience.com. I recommend this website as a valuable source of peer reviewed science on the topic of climate change. This is a post of personal opinion but I am happy to back up any of my opinions if somebody asks, though all of the facts are quite easy to find on legitimate science sites (check the list on 'the blue dot' page as well as the links below).
In all honesty I don't know I am right, all the certainty appears to be on the denialist anti-science side of the debate. They say with absolute certainty that waiting another decade or two will not irreparably alter the habitability of the planet for future generations. They are happy to promote a wait and see approach to this great global experiment of changing the composition of our atmosphere. Most if not all real science does not deal in absolutes, the physical world is based in probabilities. This doesn't mean we can't make accurate predictions and base decisions on these predictions, it means that no information is perfect and there will be a range of possible outcomes with associated probabilities. This is similar to insuring your home or your car, the likelihood of theft or accident is low but we insure nevertheless, but in climate change the probability of a bad outcome is high and we sit around and do very little.
The problem with a wait and see approach is promoting the certainty that waiting will not result in irreparable or extremely costly consequences. Most studies do not agree with this view. Consequences range from widescale migration away from coastal or newly uninhabitable areas, to increasing floods overwhelming water or sewerage treatment plants or water supplies, to wholesale adjustments to agriculture etc just to name a few. The consequences are unpredictable and costly in both money and lives. http://www.skepticalscience.com/climate-change-consequences-often-unexpected.html
What I do know is that denialists are wrong, and know they are wrong. This is due to the arguments they present, which in most cases can be easily refuted with available data and science and are often irrelevant to the science itself. Let me present a few examples.
Small numbers are not science but you often hear them spouted as proof of something by deniers, for instance "CO2 is only .04% of the atmosphere." How about iron in the body which by weight is about .006%, too little is bad for you and too much is bad for you. Or ozone which is .00006% of the atmosphere but it still protects us from UV and we were still destroying it with our puny emissions of CFC's. In science it is the effect that counts. The atmosphere is 99% nitrogen and oxygen which is basically inert to outgoing infra red so, after water vapour (which we don't control), CO2 is the largest greenhouse gas. Its effect in absorbing and re-radiating certain wavelengths of outgoing radiation is proven by the physics, proven experimentally and can be measured by satellites.
What we emit is about the only thing we know fairly well. 30 billion tonnes is emitted by us, while total atmospheric CO2 is increasing at roughly 15 billion tonnes. This tells us that far from contributing excess CO2 to the atmosphere nature is actually soaking up some of our emissions. Unfortunately what we know is that most of this excess is going into the oceans in the form of increasing acidification (30% higher). The level of CO2 has grown from 280ppm to around 390ppm in the couple of hundred years we have been emitting CO2 since the Industrial Age. As CO2 comes with different isotopes depending on its source, scientists have been able to confirm that this extra CO2 is coming from fossilised CO2 ie from burning fossil fuels.
Then there's "the climate has changed before" argument. I have yet to read a climate scientist who disputes this fact. Deniers reason that because the climate has changed naturally in the past humans cannot change it now and we are too small to make any meaningful change to the environment. I suppose that since forest fires occurred naturally in the past an arsonist could not light one now, or because it rained last week on our lawn we cannot turn a sprinkler on. Seriously? The changing of a key element in the atmosphere by 40%, increasing loss of species, polluting of our rivers, lakes and oceans (comprises over 70% percent of the earths surface and 1370 million cubic kilometres in volume), overfishing and driving to near extinction the grey whale among many others, loss of forests etc. 7 billion people and their need for accomodation, food and waste elmination has drastically changed this planet and continues to do so every day.
The other side to this argument is that Earth has been warmer, colder, had more and less CO2 etc before and is still going. Again, I have yet to see any scientist who disputes this, indeed this is where scientists get a lot of the information on how sensitive the climate is to changing CO2 and what the damage may be. Of course the planet will survive, it's a planet! What is in question is the habitability of the planet for 7 billion human beings. That is a lot different. During times when Earth was hotter and had a lot of CO2 there were many extinctions of different species, the sea level was many metres higher, the composition of the atmosphere and the climate was less friendly to humans etc. So again this one is more an argument for acting on climate change and not the other way around. Also at no other time in Earth's history has it had to provide for 7 billion humans, who like living near the coast in large fixed accommodation areas called cities. For instance about 80% of Australians live near the coast.
Some arguments are outright lies and cherry picking. For instance a denialist once compared the Arctic ice from 1975 to now claiming the ice had not changed, problem was he was comparing summer in 1975 to winter in 2011. Other tricks I have come across are using regional temperature measurements, such as from a state in the US, and presenting them as global data of a lack of temperature rises, or saying that the temperature was higher in the 1930's than now. The cherry picking normally consists of picking the period to present instead of the whole data. The common one here is choosing 1998 for temperature, 1998 being a strong el nino year, as evidence of warming having stopped. This ignores the fact that the last decade was the hottest in the instrumental record; it also ignores natural variation and any check of the entire record shows many ups and downs of decadal variations but with an obvious upward trend.
Other tricks include denigrating the main scientific organisations themselves or over-emphasising the importance of unknowns. For instance denialists will say things like "NASA predicted cooling" (they did not), or "the IPCC said it would never rain in Queensland again" (again they did not). When I push for sources I normally get a denialist blog or a fake site like NIPCC (not the IPCC). Over emphasised research includes cosmic rays and undersea volcanoes. I have had denialists tell me that CERN have proved cosmic rays determine the climate. As per normal I ask for the source and just get a denialist blog; I go to the source (CERN itself) and find out that all they have done is a small laboratory experiment that shows cosmic rays may influence cloud formation. I do some further research and find that actual data on cosmic rays correlated with temperature show that there is little if any correlation in practice.
Then let's look at the weather. I have been travelling now for five months and have covered 20 countries and 5 continents and I am told over and over, without prompting, that the weather is not normally like this. Now as denialists will tell you, extreme weather has happened before and no one weather event or change in climate is evidence of climate change (similar to the 'you can't prove a single person's lung cancer is due to smoking' argument, there are other causes and many different variables). Also extreme weather is exactly that, extreme, meaning it does not happen very often and so you need a long time to see a trend in that. But anyone can see that the last three years has not been normal; there have been increasingly severe floods, harsher droughts and more heat related weather records broken consistent with scientific predictions for climate change from a warming planet. Then look at the longer term statistics - nights warming faster than days, winters warming faster than summers - all consistent with warming caused internally and not by the sun.
I can give many more similar examples but denialists will pick on any tiny thread of an argument to sow seeds of doubt to delay action on climate change. This then gives the mining companies time to make more billions without having to account for the damage they do. This is the same thing done by big business with the smoking causes cancer debate, acid rain, the ozone hole etc, and guess what, in every case science was right and vested interests were wrong, and damage was done and lives lost during delay. But hey, they made money, right? Today 97% of climate scientists practising and publishing in the field and 100% of internationally accepted science institutions on every continent (I have seen a list of over 170) agree that human emissions are causing warming; going on past record which side should we listen to?
So while they argue about specifics denialists are ignoring the whole breadth and depth of science and data that point in the same direction. If any one argument is shaky it has loads of others to back it up. To sum up the indicators of global warming due to increasing CO2 emissions by humans I would list the following as my top 11 indicators:
1) CO2 having cycled between 180 and 280ppm for about a million years and then risen to 390+ ppm since the Industrial Revolution.
2) Temperatures increasing over the instrumental record culminating in the hottest decade on record.
4) Acidification of the oceans increasing by 30% since we've been spewing out CO2.
5) Moisture in the atmosphere increased by 4%.
6) Nights warming faster than days.
7) Winters warming faster than summers.
9) The lower atmosphere (troposphere) warming while the upper atmosphere (stratosphere) is cooling, consistent with warming by CO2 and not the sun.
10) Increasing extreme weather events of the type consistent with climate change. That extra 4% of moisture fuels storms and floods and the extra heat increases drought and heat waves in prone areas.
There are many more, but I am not a scientist, only a computer teacher. I have also been asked, why do I care? I care because I have two beautiful children and one grandson so far and I worry gravely about the world they will be left to live in, how difficult it may be for them and what hardships they will have to endure the longer we take to do something. It is ok to provide for the financial future of our children, but that won't be much help if the world they have left is largely uninhabitable.
Useful links to help you decide for yourself:
Extremely thorough exlanation of the evidence proving that the source of the extra CO2 is from the burning of fossil fuels.
National Snow and Ice Data Centre
Sea level rises
Arctic Report Card
NASA key indicators
NOAA (National Oceanic and Atmospheric Administration) Climate Monitoring
Excellent compilation of climate related graphs including ocean acidity, temperatures, sea level, ice realted data etc.
World Meteorological Organisation Preliminary report on the last decade.
Berkeley Earth Surface Temperature Study. A study done by a previous skeptic with funding from the fossil fuel industry attempting to disprove the temperature trend by analysing 1.6 billion records. He found that they were correct and now states that we are warming and it is almost exclusively caused by human emissions.
All the graphics were taken from skepticalscience.com/graphics