Photo: IPCC report shows action on climate change is critical

An increase in global average temperatures greater than 2 C above pre-industrial levels would result in further melting of glaciers and Arctic ice, continued rising sea levels, more frequent and extreme weather events, difficulties for global agriculture and changes in plant and animal life, including extinctions (Credit: mariusz kluzniak via Flickr)

By David Suzuki with contributions from Ian Hanington, Communications Manager

The Intergovernmental Panel on Climate Change just released the first of four chapters of its Fifth Assessment Report. It shows scientists are more certain now than in 2007 when the Fourth Assessment was released that humans are largely responsible for global warming — mainly by burning fossil fuels and cutting down forests — and that it's getting worse and poses a serious threat to humanity. It contains hints of optimism, though, and shows addressing the problem creates opportunities.

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The IPCC was set up in 1988 by the World Meteorological Organization and UN Environment Programme at the request of member governments. For the recent study, hundreds of scientists and experts worldwide combed through the latest peer-reviewed scientific literature and other relevant materials to assess "the state of scientific, technical and socio-economic knowledge on climate change, its causes, potential impacts and response strategies."

Scientists are cautious. That's the nature of science; information changes, and it's difficult to account for all interrelated factors in any phenomenon, especially one as complicated as global climate. When they say something is 'extremely likely' or 95 per cent certain — as the latest report does regarding human contributions to climate change — that's as close to certainty as science usually gets. Evidence for climate change itself is "unequivocal".

According to the latest installment, which cites 9,200 scientific publications in 2,200 pages, "It is extremely likely that human activities caused more than half of the observed increase in global average surface temperature from 1951 to 2010." It also concludes oceans have warmed, snow and ice have diminished, sea levels have risen and extreme weather events have become more common.

The report also dismisses the notion, spread by climate change deniers, that global warming has stopped. It has slowed slightly in recent years, scientists say, because of natural weather variations and other possible factors, including increases in volcanic ash, changes in solar cycles and, as a new scientific study suggests, oceans absorbing more heat.

An increase in global average temperatures greater than 2 C above pre-industrial levels would result in further melting of glaciers and Arctic ice, continued rising sea levels, more frequent and extreme weather events, difficulties for global agriculture and changes in plant and animal life, including extinctions. The report says we'll likely exceed that threshold this century unless we choose to act.

This means a strong, concerted global effort to combat climate change is necessary to protect the health of our economies, communities, children and future. That will cost us, but far less than doing nothing. Although governments of almost 200 countries agreed global average temperature increases must be kept below 2 C to avoid catastrophic warming, we are on track for the "worst case scenario" outlined by the first assessment report in 1990. Research indicates it's possible to limit warming below that threshold if far-reaching action is taken. We can't let skeptics sidetrack us with distortions and cherry-picking aimed at creating the illusion the science is still not in.

The reasons to act go beyond averting the worst impacts of climate change. Fossil fuels are an incredibly valuable resource that can be used for making everything from medical supplies to computer keyboards. Wastefully burning them to propel solo drivers in cars and SUVs will ensure we run out sooner rather than later.

Working with other nations to meet science-based targets to cut global warming pollution and create clean, renewable energy solutions would allow us to use our remaining fossil fuel reserves more wisely and create lasting jobs and economic opportunities. That's why the David Suzuki Foundation is working with the Trottier Energy Futures Project to identify clean-energy opportunities for Canada.

Shifting to cleaner energy sources would also reduce pollution and the environmental damage that comes with extracting coal, oil and gas. That would improve the health of people, communities and ecosystems, and reduce both health-care costs and dollars spent replacing services nature already provides with expensive infrastructure.

The IPCC report gathers the best science from around the world. It's clear: There's no time to delay. The first chapter examines the current science of climate change, the second will look at impacts and the third will consider strategies to deal with the problem. A report synthesizing the three chapters will be released in 2014. We must take it seriously.

October 3, 2013

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Jan 16, 2017
9:53 AM

thank you for the powerful information

Dec 14, 2015
3:35 PM

I’ve been staying on the sidelines of the issue(s) around ‘climate change’, but decided it is time to try to make some sense of it. I’d be pleased if you could help.

I can easily see the actual impact of severe weather on people and environment. It seems it would be preferable to reduce the severity / frequency of such events, if we could. What data is there to show the frequency / severity compared with long-term?

It makes sense to me that higher temperatures might drive more severe weather. We certainly see this in the ‘normal’ weather with very hot summer days giving way to thunderstorms and even hail. But in the global temperature data that I can find, it appears that temperatures over the last several decades may be up a little, but well within the historical range, and possibly showing a tendency toward a pending and significant drop, with the really long-term charts suggesting that we are overdue for a new ice age. What would that do to weather, climate change, people and the environment?

The lynch-pin in most of the present ‘action on climate change’ seems to be a belief that there is a direct cause and effect relationship between CO2 content in the atmosphere and global temperature and therefore climate change. I think that I’ve seen some scientific measurement of heat transmission properties of gasses, which rates CO2 as one of the gasses more resistant to heat transfer and considered to trap heat in the earth’s atmosphere. Of course, its a big step to go from bench-scale measurement of a material’s physical properties to a real-life impact at such low concentration (< 0.1%). Has there been any larger system experiments / measurements to validate the theory? As far as I can tell from the ice core data (that’s the only source of long-term data that I have seen) temperatures come down hundreds of years before CO2 comes down and similarly, temperatures go up hundreds of years before the CO2 goes up. And lately the CO2 has continued to go up without the temperatures going up. It doesn’t seem to be a very strong cause and effect being lead by CO2. I think this is my biggest hang-up and would be interested in how you see this.

Jun 14, 2015
10:09 AM

Last year, 2014, the world witnessed the Atlantic ocean spilling into the New York City subway system as sea levels continue to rise due to global warming. Over a billion people around the world that live on oceanic and major river shore lines are in imminent danger of losing their habitat. We live at a time of the end of an epoch

Mar 31, 2015
1:59 PM

Perhaps we need to put hard numbers to the costs of climate warming. I thought I had read that climate warming was causing about $one trillion per year globally. Does that sound correct? Who pays?

Feb 04, 2015
4:16 PM

shifting to cleaner energy seems like a no-brain er. maybe that’s the problem..

May 08, 2014
1:27 PM

I used to be a fan, but you lost it sometime ago. Facts will always beat out conjecture. I should not need to believe climate change, it should be without a doubt based on observation and measurement and not theory.

Feb 12, 2014
2:19 PM

this climate change is messed up

Jan 05, 2014
1:49 PM

Hello David Not a fan of climate change what so ever, I think your skeptical of what the sun adds and subtracts. You place far to much wow factor on things that don’t mean beans.. Stat warm turn up the heat and enjoy.

Jan 03, 2014
6:00 AM

Those who have had a conversion experience and became born again “Believers” to the horrors of AGW might want to take a look out their windows and witness the record breaking LOW temperatures across the continent. Oh yes, this is just ‘weather’! I got it.Temperatures have NOT risen in 15 years, despite rising levels of CO2. Practically all ‘models’ that the IPCC came up with years ago are all wrong, but the Believers who have so much at stake in their newly found religion will only find one more way to say this current storm, called Hercules, also is a result of AGW. Hard to argue with converts.

Denier Tim

Jan 02, 2014
10:16 AM

Its pretty cold here in Canada right now…Coldest winter in many years…..!!!….

To The Horror Of Global Warming Alarmists, Global Cooling Is Here!!!

Dec 25, 2013
3:27 PM

Although this article tries to determine that humans are a major contributing factor, the IPCC is not the best source for this information. The IPCC is mandated to only review MAN-MADE changes in the climate, they do not accurately measure other inputs such as volcanoes which cause massive changes to worldwide. Essentially this article is leftwing fear-mongering.

Dec 18, 2013
2:24 PM

Hello David, I agree with the critical, immediate decision on the response for a climate change. People should have realized already the change in the climate, and that its getting worst every year. We need to look at the future of our next generations to come, and not be selfish, and “ignore what can become a disaster.”

Nov 29, 2013
12:11 PM

I’m a big fan of your beard

Nov 27, 2013
6:45 AM

Do volcanoes have anything to do with global warming. Did the setting off of 2053 atomic bombs on this planet have anything to do with global warming

Nov 04, 2013
5:14 AM

So what do we do? This is my question. My little boy is 3 and I am increasingly distraught over what he will face in his life time. At the same time, I feel powerless in the face of these overwhelming issues. Where do we start and how do we move forward to create this change?

Oct 09, 2013
4:12 PM

fruit fly time

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