UN climate report offers stark warnings, hope (Update)

UN panel adopts landmark climate report
In this Wednesday, Dec. 16, 2009 file photo, steam and smoke rises from a coal burning power plant in Gelsenkirchen, Germany. After an all-night session, the U.N.'s expert panel on climate science is scrambling to finish a report on global warming that's meant to guide negotiations on a new international climate deal. (AP Photo/Martin Meissner, File)

Climate change is happening, it's almost entirely man's fault and limiting its impacts may require reducing greenhouse gas emissions to zero this century, the U.N.'s panel on climate science said Sunday.

The fourth and final volume of the Intergovernmental Panel on Climate Change's giant climate assessment didn't offer any surprises, nor was it expected to since it combined the findings of three earlier reports released in the past 13 months.

But it underlined the scope of the climate challenge in stark terms. Emissions, mainly from the burning of fossil fuels, may need to drop to zero by the end of this century for the world to have a decent chance of keeping the temperature rise below a level that many consider dangerous. Failure to do so, which could require deployment of technologies that suck greenhouse gases out of the atmosphere, could lock the world on a trajectory with "irreversible" impacts on people and the environment, the report said. Some impacts are already being observed, including rising sea levels, a warmer and more acidic ocean, melting glaciers and Arctic sea ice and more frequent and intense heat waves.

Amid its grim projections, the report also offered hope. The tools needed to set the world on a low-emissions path are there; it just has to break its addiction to the oil, coal and gas that power the global energy system while polluting the atmosphere with heat-trapping CO2, the chief greenhouse gas.

"We have the means to limit climate change," IPCC chairman Rajendra Pachauri said. "The solutions are many and allow for continued economic and human development. All we need is the will to change, which we trust will be motivated by knowledge and an understanding of the science of climate change."

The IPCC was set up in 1988 to assess global warming and its impacts. The report released Sunday caps its latest assessment, a mega-review of 30,000 climate change studies that establishes with 95-percent certainty that nearly all warming seen since the 1950s is man-made.

Today only a small minority of scientists challenge that mainstream conclusion that climate change is linked to human activity.

Sleep-deprived delegates approved the final documents Saturday afternoon after a weeklong line-by-line review in Copenhagen that underscored that the IPCC process is not just about science. The reports must be approved both by scientists and governments, which means political issues from U.N. climate negotiations, which are nearing a 2015 deadline for a global agreement, inevitably affect the outcome.

The rift between developed and developing countries in the U.N. talks opened up in Copenhagen over a box of text that discussed what levels of warming could be considered dangerous. After a protracted battle, the delegates couldn't agree on the wording, and the box was dropped from a key summary for policy-makers to the disappointment of some scientists.

"If the governments are going to expect the IPCC to do their job," said Princeton professor Michael Oppenheimer, a lead author of the IPCC's second report, they shouldn't "get caught up in fights that have nothing to do with the IPCC."

The omission of the box meant the word "dangerous" disappeared from the summary altogether. It appeared only twice in a longer underlying report compared to seven times in a draft produced before the Copenhagen session.

But the less loaded word "risk" was mentioned 65 times in the final 40-page summary.

"Rising rates and magnitudes of warming and other changes in the climate system, accompanied by ocean acidification, increase the risk of severe, pervasive, and in some cases irreversible detrimental impacts," the report said.

World governments in 2009 set a goal of keeping the temperature rise below 2 degrees C (3.6 F) compared to before the industrial revolution. Temperatures have gone up about 0.8 C (1.4 F) since the 19th century.

Meanwhile, emissions have risen so fast in recent years that the world has already used up two-thirds of its carbon budget, the maximum amount of CO2 that can be emitted to have a likely chance of avoiding 2 degrees of warming, the IPCC report said.

"This report makes it clear that if you are serious about the 2-degree goal ... there is nowhere to hide," said Alden Meyer of the Union of Concerned Scientists, an advocacy group. "You can't wait several decades to address this issue."

Pointing to the solution, the IPCC said the costs associated with mitigation action such as shifting the energy system to solar and wind power and other renewable sources and improving energy efficiency would reduce economic growth only by 0.06 percent annually.

And Pachauri said that cost should be measured against the implications of doing nothing, putting "all species that live on this planet" at peril.

The report is meant as a scientific roadmap for the U.N. climate negotiations, which continue next month in Lima, Peru. That's the last major conference before a summit in Paris next year, where a global agreement on climate action is supposed to be adopted.

The biggest hurdle is deciding who should do what, with rich countries calling on China and other major developing countries to take on ambitious targets, and developing countries saying the rich have a historical responsibility to lead the fight against warming and to help poorer nations cope with its impacts. The IPCC carefully avoided taking sides in that discussion, saying the risks of climate change "are generally greater for disadvantaged people and communities in countries at all levels of development."

Explore further

Climate rescue mission 'not hopeless': IPCC chief (Update)

© 2014 The Associated Press. All rights reserved.

Citation: UN climate report offers stark warnings, hope (Update) (2014, November 2) retrieved 23 August 2019 from https://phys.org/news/2014-11-panel-landmark-climate.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.

Feedback to editors

User comments

Nov 02, 2014
If you consider all those living in every corner of the world now dependent on: heating generated by gas, oil, coal, charcoal; electricity generated by gas, oil and coal; gasoline produced from oil; affordable food prices made possible by the relatively low costs associated with farming and the transportation of agricultural commodities, thanks to the relatively low cost of petroleum products, you will understand the extent of the disaster we'd all be facing if these insane recommendations were adopted.

For more on this issue, see http://amoleinthe...tor.html and related posts on the same blog.

Nov 02, 2014
Victorag does not understand how technologies get integrated into societies. It is not wholesale, all or nothing, it is the gradual replacement of units and systems which no longer make economic or social sense.

After a while, we then realize we have a new and better system. I have been in this field most of my life (energy and the environment), and welcome the evolution to a better existence.

Nov 02, 2014
The reality is that behavior will not change.

We can see how temperature, a secondary effect of man's burning of fossil fuels, has a very strong linear correlation to inflation adjusted GDP

(Set range ~1950 to now)

And then we can inspect the Global Warming effect of CO2 vs Water here:
We see H2O overwhelming the spectrum, and even overlapping and dramatically contributing at CO2's single absorption band.

So if water is not a significant contributor to the issue of AGW, clearly CO2 is much less so, clearly their is a variable the state of the art is unaware of, that is yet related to GDP.

Nov 02, 2014
As I replied in another thread: Change is coming. Look at the recent changes in our treatment of gays. Look into our attitudes toward smoking tobacco. Look at our attitudes toward cannabis.

The change will come after it hits the recalcitrants in the face.

Nov 02, 2014
Yet we can partially quantify mankind's contribution to the environment by calculating the amount of energy added to the Earth system:
We have a 6cm rise in Earths Oceans. 6cm X ocean area X latent heat of ice = 6 x 3.61e12 x 333 Joules/Gram = 7.2 e 15 Joules. (a Nuke is 10e13 joules)

And you can see how ocean level rise corresponds to ownership in cars:
Note the changes around 1940.

Nov 02, 2014
Note the rapid industrialization in preparation for world-wide war in 1940. Few cars were on the road in the early to late 1940's.

Nov 02, 2014
Now, I can confidently say that the anthropogenic global warming will only stop many years (rather decades) after entire fossil fuel stock inside the Earth have been consumed, when there is nothing left to burn in the name of fossil fuels.

On one hand they say this is the only planet to live, on the other hand they are digging more and more fossil fuels, professors collaborating with oil companies. What kind of hypocrisy is this?

Nov 02, 2014

"Why is this in a science related website?"

A question only an idiot would ask.

Nov 03, 2014

On one hand they say this is the only planet to live, on the other hand they are digging more and more fossil fuels, professors collaborating with oil companies. What kind of hypocrisy is this?

The problem is responsibility, let me rephrase this:

"On one hand WE say this is the only planet to live, on the other hand WE are digging more and more fossil fuels"

You can't blame a company for selling the goods you want to consume, neither will they put themselves out of business because it's good for the environment. It should be us willing to choose an alternative for fossil fuels.

Nov 03, 2014
Michael Oppenheimer, a lead author of the IPCC..


Nov 03, 2014
Yes, I can. Selling us something we do not really need or something not good for us is indicative of character, which you approve.

You must be in "business", where morality is formable and transient.

Nov 03, 2014
Their goal is to reduce population and limiting cheap energy would sure help that along. The only threat that humans face from climate change is cooling and glaciation. Our tiny CO2 contribution to the atmosphere may delay or prevent the return to normal glacial conditions, but I doubt it.

Nov 03, 2014
On the contrary, I'm not allowing myself to believe this is someone else's fault and we can't do anything about it. I'm an energy consumer and slowly making the steps to become less fossil fuel dependent.

A company is not a living entity with morals and we shouldn't expect that from it either. Fact is, they're not selling unless we're buying and we have the power to stop buying.

Nov 03, 2014
You have good points. I have re-insulated my house, installed condensing furnace and instantaneous water heater, and will use solar. Right now, I only use it on my pergola, charged by the sun during the day. It gets hot here, often well over 100 degrees, but we do not have A/C. I use diurnal temperature changes to control the house conditions.

I have two water systems, one from the San Joaquin Delta, which is not treated, filtered, or pumped, and is full of bird and fish manure for the plants. Our combined power bills are usually around $100 month.

Nov 03, 2014
You'll notice gas prices are as low as they have ever been, especially inflation adjusted...

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more