Make no mistake, climate change is the greatest long-term threat to human health.
Heat stress, extreme cold, human conflict and mosquito and water-borne infections are the biggest dangers of a warmer world.
Extreme heat kills and very recently we’ve seen intense heatwaves in India, Pakistan, Iran and Middle Eastern countries. Humans might adjust, provided there’s access to base-load power and air-conditioning, but if you live in a slum, or a remote village, there’s no escape. It’s always the poor who are most vulnerable.
Climate scientists have been so beaten up over the years they have become very cautious and moderate about what they say. In reality, we could be looking at a temperature rise of 2 to 6 degrees Celsius over the next 100 years.
It’s difficult for people to get their heads around. If it’s 45C at the height of summer here now, what happens if it’s 51C? A whole lot of people will die, that’s what.
The second threat, surprisingly, is cold stress. It’s related to changes in ocean temperatures and the slowing of the Atlantic Conveyer, the Gulf Stream that keeps the west coast of Britain and east coast of America warm. As the current slows, we get more extreme cold events.
And, because of other changes in weather patterns, we’ve seen enormous dumpings of snow on the east coast of the United States of America.
Then there’s flooding. Extreme rainfall events lead to flooding, a breakdown of the sewerage systems and the greater likelihood of sewage contamination and infections. Ocean flooding is also leaking salt into aquifers and contaminating drinking water. These effects are already being seen in some low-lying countries.
The biggest problem, apart from the direct affect of heat on people, remains to be seen - and that’s how habitable some parts of the world will become.
We’re facing enormous numbers of climate refugees.
With rising sea levels and more flooding events, come water-borne infections, like typhoid and cholera. Mosquito-borne infections will move further away from the equator.
We can expect to see malaria in northern Australia and a lot more dengue coming further south. We might see Japanese encephalitis.
But these are not insurmountable problems; with the resources and institutional wherewithal, we can handle them.
Even more worrying is the geopolitical landscape taking shape as populations compete for land and water.
New York Times journalist Tom Friedman has looked at recent migration patterns and found that the major political breakdowns in the Middle East have been preceded by extreme food prices due to drought.
In a less stable world, issues like the prospects of nuclear war are of growing concern through growing political instability. This was one area of major concern highlighted in the recent Lancet Climate Commission on the health effects of climate change.
Pakistan, India and Bangladesh have enough nuclear weapons to wipe out most of the people on the planet. And if Daesh gets hold of even the most unsophisticated nuclear device, it will be a very bad day for humanity.
We are currently seeing a breakdown in the global social order and if climate change goes ahead as predicted, that will just get worse.
Hopefully the Paris talks will herald a new beginning, but we can’t expect too much in the short term.
Most international leaders recognise the need to cut emissions, but getting any real action is a major problem.
Some countries are stepping back a little. Germany, for example, operated nuclear reactors for decades and even though they are doing well with renewables, they are turning back to coal because of what happened in Fukushima, Japan.
Australia, like most other countries, has a responsibility to cut greenhouse gases.
The carbon tax was the right thing to do and it didn’t actually cost that much. The present scheme, direct action, is a step in the right direction, but we really need a global price on carbon.
Our Prime Minister Malcolm Turnbull argues that if we don’t supply coal, someone else will, but this is the drug dealer’s defence. We need to move towards a low-carbon economy.
Australia is still seen by the world as a mine and a farm.
We are in a difficult situation, because we have a small population and our economic reliance on coal exports remains so high, even though we live on the Earth’s biggest solar and wind resource.
Thankfully, after five years of listening to the negativity of our former Prime Minister, the tone of the conversation has changed for the better.
Malcolm Turnbull is not saying anything exceedingly different, but he is speaking positively and intelligently. If he wins the next election, I hope he will become less sympathetic to the fossil fuel industries.
Essentially, the climate problem is driven by burning greenhouse gases and is exacerbated by the fact so many of us are making major demands on dwindling resources.
Overall, we have to take a science-based view of climate and the environment. Science is not perfect and we can’t perfectly predict the future.
But we have to operate within the context of our best understanding. No one thinks we’re going to drop coal overnight, but we need to wean off fossil fuels.
Can we really generate sustainable base-load power from renewables? I don’t know, but we need to think about this seriously now. The Australian people aren’t going to accept power outages.
You can’t operate a significant air-conditioning unit solely on renewables and it’s clear we’re going to need air-conditioning in this country.
Sustainable cities will be the key to our future.
In April this year, I was at a Nobel symposium on the sustainable city, held in Hong Kong. Sustainable cities are such an important issue that I hope makes some progress post-Paris.
There is a real opportunity for Australia to mandate sustainable building codes, so our architects and engineers naturally operate in that mode. It’s a great shame we’re not already doing this, because we could sell that expertise in Asia.
Climate change fatigue is a real and growing problem. People are sick of hearing about it.
There is tremendous information available about climate change that is free and at your fingertips. If you want to know about it, start with Wikipedia. But despite this, what most people hear is just gossip over the back fence.
Scientists have to be very careful to stop coming across as wowsers. No one likes to be lectured.
The truth is, none of us really want to confront the issue. We all indulge in wishful thinking because it’s too hard.
Human beings are the only species on the planet with the capacity for denial.
We are the only species who understands the inevitability of our own death. We take risks.
Denial allows us to sail our ships beyond the horizon, to jump out of a plane with parachute. It’s the natural human condition.
The antidote to denial about the realities of nature, is science.
Most people look at the world through the filter of their general belief system. The beauty of science is that it forces you to examine without those pre-conceptions.
Science requires us to take the “filters off”, to measure and write up our findings, for others to critique, test and probe.
The best hope we have of getting real action on climate lies with young people.
If I were 25-years-old, I’d be designing iPad and PlayStation games about climate change to get more people engaged.
All who care about this, old or young, can use technology and social media in a positive way to reach out to those who may be unconvinced, or remain uninvolved.
With so much misinformation out there, from the right and the left, we have to encourage people to go to authoritative sources that inform their thinking by providing sound scientific information
Professor Peter Doherty’s new book on probing climate and evidence-based reality, The Knowledge Wars, is available now from Random House.
Banner image: Ernie Penaredondo Flickr