The World Meteorological Organisation says the warming effect of long-lived greenhouse gasses has increased by 41% since 1990

Content supplied by the WMO

Levels of heat-trapping greenhouse gases in the atmosphere have reached another new record high, according to the World Meteorological Organisation (WMO). There is no sign of a reversal in this trend, which is driving long-term climate change, sea level rise, ocean acidification and more extreme weather.

The WMO Greenhouse Gas Bulletin showed that globally averaged concentrations of carbon dioxide (CO2) reached 405.5 parts per million (ppm) in 2017, up from 403.3 ppm in 2016 and 400.1 ppm in 2015. Concentrations of methane and nitrous oxide also rose, whilst there was a resurgence of a potent greenhouse gas and ozone depleting substance called CFC-11, which is regulated under an international agreement to protect the ozone layer.

Since 1990, there has been a 41% increase in total radiative forcing – the warming effect on the climate - by long-lived greenhouse gases. CO2 accounts for about 82% of the increase in radiative forcing over the past decade, according to figures from the US National Oceanic and Atmospheric Administration quoted in the WMO Bulletin.

“The science is clear. Without rapid cuts in COand other greenhouse gases, climate change will have increasingly destructive and irreversible impacts on life on Earth. The window of opportunity for action is almost closed,” said WMO Secretary-General Petteri Taalas.

“The last time the Earth experienced a comparable concentration of CO2 was 3-5 million years ago, when the temperature was 2-3°C warmer and sea level was 10-20 meters higher than now,” said Mr Taalas.

The WMO Greenhouse Gas Bulletin reports on atmospheric concentrations  of greenhouse gases. Emissions represent what goes into the atmosphere. Concentrations represent what remains in the atmosphere after the complex system of interactions between the atmosphere, biosphere, lithosphere, cryosphere and the oceans. About a quarter of the total emissions is absorbed by the oceans and another quarter by the biosphere.

A separate Emissions Gap Report by UN Environment (UNEP), to be released on 27 November, tracks the policy commitments made by countries to reduce greenhouse gas emissions.

The WMO and UNEP reports come on top of the scientific evidence provided by the Intergovernmental Panel on Climate Change (IPCC) Special Report on Global Warming of 1.5°C. This said that net emissions of COmust reach zero (the amount of COentering the atmosphere must equal the amount that is removed by sinks, natural and technological) around 2050 in order to keep temperature increases to below 1.5°C. It showed how keeping temperature increases below 2°C would reduce the risks to human well-being, ecosystems and sustainable development.

“COremains in the atmosphere for hundreds of years and in the oceans for even longer. There is currently no magic wand to remove all the excess CO2 from the atmosphere,” said WMO Deputy Secretary-General Elena Manaenkova.

“Every fraction of a degree of global warming matters, and so does every part per million of greenhouse gases,” she said.

Together, the reports provide a scientific base for decision-making at the UN climate change negotiations, which will be held from 2-14 December in Katowice, Poland. The key objective of the meeting is to adopt the implementation guidelines of the Paris Climate Change Agreement, which aims to hold the global average temperature increase to as close as possible to 1.5°C.

“The new IPCC Special Report on Global Warming of 1.5°C shows that deep and rapid reductions of emissions of carbon dioxide and other greenhouse gases will be needed in all sectors of society and the economy. The WMO Greenhouse Gas Bulletin, showing a continuing rising trend in concentrations of greenhouse gases, underlines just how urgent these emissions reductions are,” said IPCC Chair Hoesung Lee.

Integrated Global Greenhouse Gas Information System

The Greenhouse Gas Bulletin is based on observations from the WMO Global Atmosphere Watch Programme, which tracks the changing levels of greenhouse gases as a result of industrialization, energy use from fossil fuel sources, intensified agricultural practices, increases in land use and deforestation. Globally averages presented in the Bulletin are representative for the global atmosphere.

The urgency of actions to reduce greenhouse gas emissions requires more tools at national and sub-national level to support stakeholders in taking effective and efficient actions.

Recognizing this need, WMO has initiated the development of observational based tools that can guide the emissions reduction actions and confirm their results, for instance in the oil and gas sector.

A new Integrated Global Greenhouse Gas Information System (IG3IS) provides the framework for the development and standardization of the observational based tools. IG3IS is implemented by countries on a voluntary basis and will feed into the national emission reporting mechanism to the UN Framework on Climate Change and the annual Conference of the Parties.

Key Findings of the Greenhouse Gas Bulletin

Carbon dioxide

Carbon dioxide is the main long-lived greenhouse gas in the atmosphere. Concentrations reached 405.5 ppm in 2017, 146% of the pre-industrial era (before 1750). The increase in COfrom 2016 to 2017 was about the same as the average growth rate over the last decade. It was smaller than the record leap observed from 2015 to 2016 under the influence of a strong El Niño event, which triggered droughts in tropical regions and reduced the capacity of “sinks” like forests and vegetation to absorb CO2.  There was no El Niño in 2017.


Methane (CH4) is the second most important long-lived greenhouse gas and contributes about 17% of radiative forcing. Approximately 40% of methane is emitted into the atmosphere by natural sources (e.g., wetlands and termites), and about 60% comes from human activities like cattle breeding, rice agriculture, fossil fuel exploitation, landfills and biomass burning.

Atmospheric methane reached a new high of about 1859 parts per billion (ppb) in 2017 and is now 257% of the pre-industrial level. Its rate of increase was about equal that observed over the past decade.

Nitrous Oxide

Nitrous oxide (N2O) is emitted into the atmosphere from both natural (about 60%) and anthropogenic sources (approximately 40%), including oceans, soil, biomass burning, fertilizer use, and various industrial processes.

Its atmospheric concentration in 2017 was 329.9 parts per billion. This is 122% of pre-industrial levels. It also plays an important role in the destruction of the stratospheric ozone layer which protects us from the harmful ultraviolet rays of the sun. It accounts for about 6% of radiative forcing by long-lived greenhouse gases.


The Bulletin has a special section devoted to CFC-11 (trichlorofluoromethane). This is a potent greenhouse gas and a stratospheric ozone depleting substance regulated under the Montreal Protocol. Since 2012 its rate of decline has slowed to roughly two thirds of its rate of decline during the preceding decade. The most likely cause of this slowing is increased emissions associated with production of CFC-11 in eastern Asia.

This discovery illustrates the importance of long-term measurements of atmospheric composition, such as are carried out by the Global Atmosphere Watch Programme, in providing observation-based information to support national emissions inventories and to support agreements to address anthropogenic climate change, as well as for the recovery of the stratospheric ozone layer.

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I smell another tax coming.

The cudgel may be the only tool left, after the storms and droughts have failed to convince..

Ho Hum the world is really going to end this time we had better apply for another Govt grant to fund more research.

For years, the increase in the number of Chinese coal-fired power stations has been criticised. Now environmental groups say China is also backing dozens of coal projects far beyond its borders.

The Chinese-supported coal projects are under way or planned as far afield as South America, Africa, southeast Asia and the Balkans. Christine Shearer is an analyst with the group CoalSwarm, which tracks coal developments, and she is scathing about the implications.

"These projects are not compatible with limiting global warming to 1.5C or 2C," she said, referring to the two targets of the Paris Agreement on climate change. She says that Chinese financial institutions are filling a gap left by Western banks and agencies deciding to limit their involvement in coal.

From the "succeeding" New York Times
An unstoppable tide, tragedy of the commons

Who do you believe ?? IPCC have been busted many times altering data - check this video out tells a different true story about what's happening -

The truth about global warming

Dr. Patrick Michaels, director of the Center for the Study of Science at the Cato Institute, provides insight into the debate over climate change and the political games played to create policy.

Very good interview!
He explains that all models, except the Russian model, are parameterised (meaning fudged).
A lot more important info in the interview.

antonymouse - Interesting thanks

In 2012, the Koch Brothers and Ed Crane of the Cato Institute had a “bitter falling-out over management and philosophical differences.” The Koch Brothers, who controlled roughly half of the Cato Institute through “shareholder seats,” had decided to sue the Cato Institute to gain control over an additional seat of a shareholder who had died, which would give the Kochs more control within the organization.


If you can wade through the Scientific Advice for Policy Makers paper you will see that there is no reference to the 1.5 or 2.0 deg targets.

It is purely the construct of the politicians.

The paper also points out it is not possible to project future temperatures due to the complex nature of the problem.

Doesn’t stop the Pollies - We need saving !

No mention of the benefits of supposedly warmer world. Higher growth in agriculture and areas of the world eg Russia having greater productivity due to longer growing seasons.

The independently constructed satellite record of global average temps shows no warming in 20 years. Yet as warming is supposedly a function of CO2 it is very difficult to reconcile why levels keep rising in a near straight line - but temperatures simply do not follow.


With no sunspots today - a very unusual state of affairs, we will sooon be seeing cooling if the Maunder and Dalton minimums are correlated with temperature as they certainly were in the previous century.

That because the scientists job is to provide the facts , the politician's job is to make targets and legislate to meet them.

I stop reading as soon as they say "denier".

ZS: always good to keep reading

Me to the word 'denier' makes it like a religious following, fear the perfect emotion to control and scare the masses just like religion. Beening a forestry/carbon credit owner I have experienced the insanity of the so called man made global warming it's a crusade to make money. Oddly enough I have made money from it which really feels weird.Carbon Credits invented by Enron when Al Gore was CEO - enough said !

Is that the same Al Gore who confidently predicted our children would never see snow again ?

What part of the science behind climate change don't you understand? The bit Trump explained to you perhaps?

The part showing a diagram used by our Commissioner for the Environment and many others with IR heat radiating from the warmer surface to the cooler atmosphere - no problem with that - but then shows the cooler atmosphere radiating back to the surface and heating it in direct conflict with the laws of thermodynamics.

The diagram showing the heat convecting up to the atmosphere but not showing the colder atmospheric air flowing down to cool.

The fact that all models use a feedback multiplier of ~ 3 to account for more moisture clouds when the ERBE satellite showed warmer areas radiate more heat to space - exactly as you would expect - showing a negative feedback.

The fact that the IPPC is not allowed to consider other variables such as orbital mechanics, sun spots as contributing to earth's temperatures.

The fact that all past projections of temperature from the IPPC have been wildly inaccurate - the measured temperatures have been much less than each of their past forecasts.

Best you alert the global science community that clever old you has found an error in their research. Thanks, I can now relax and carry on as usual. if you can post details, I'll nominate you for a Nobel award.

Tell the polar bears that... JB

4 times more than 50yrs ago . not doing so bad

Heat transfer is hard to understand, because we see the world heat and cool , we think cold and hot.
Its all relative and to do with degree of "radiability" or transferability (don't know the correct term), rather than the actual temp of an object. An eg would be touching a metal object and a plastic object of the same temp , the metal one will feel cooler or hotter than the plastic one of the same temp. so it is possible for a cold object to transfer heat to a hot object.

" … so it is possible for a cold object to transfer heat to a hot object."

Where do I start ?

All objects radiate at a frequency based on their temperature. So a warmer - as in higher temperature - and a cooler body - as in lower temperature - will both be radiating at different frequencies - but the NET radiation balance will always be energy flowing from the warmer to the cooler body.

So it is totally impossible for a cold object to transfer heat to a hot object - if it were one could easily construct a perpetual motion machine which the law of thermo dynamics prevent.

Thus while the warmer surface of the earth will radiate and heat the cooler atmosphere to a degree - it is totally impossible for the cooler atmosphere to increase the temperature of the earth's surface as shown in energy balance diagrams referred to by re-radiating back from the cooler atmosphere to the surface.

Did you just make that up, that Gore was CEO of Enron? He had nothing to do with it, that I can find. It was Lay and Skilling essentially. The only political figures I can find who had some [minor] involvment were Cheney, Rove, and a handful of others on the Republican side. Not a good idea just to make stuff up to fit your views.

David that was suppose to read - Carbon Credits ( in the Kyoto Protocol ) were invented by Enron CEO and Al Gore !

Correction - Al Gore and Enron had nothing whatsoever to do with Carbon Credits !

Carbon credits were a concept initiated by a forestry team ex New Zealand sent to the very first IPPC meeting Rio in 1991 to ensure the credits generated by plantation forestry were accepted. Included Dr Wink Sutton ex Fletcher Forests.

The moment you mention religion in this debate youve already aligned with the heartland types. Irony being the last lot who spoke like that were the NZCSC, now defunct after being unable to put a clear case together in court in the NIWA case. Sadly this is typical.

That 1st article is very poor. Written by a nobody it puts down anyone asking questions as liars or old fools who are racist too. If like myself you think the govt should be raising taxes to deal with a real risk from climate change then you also have an obligation to answer all doubts because you are asking to spend their taxes.
Racism is independent of climate change and certainly as an elderly person I hear racism from my peer group but it seems to be far more prevalent in young people - see the UK labour party and when you see physical attacks on immigrants it is by young skinheads not white haired pensioners with zimmer frames.

Here is the Trump Adminmistration report out today:

And here is their Summary:

Sceptics should read this stuff. This is what the Trump Administration is saying. Yes, you read that right.

It is a big document so read the summary. It does seem to be rather weak - with references to USA coral reefs (surely insignificant) and no mention of say 50 million Bengalis becoming homeless. This is the end of the summary just to show how it fails to estimate the costs and benefits.
""These and other climate-related impacts are expected to result in decreased tourism revenue in some places and, for some communities, loss of identity. While some new opportunities may emerge from these ecosystem changes, cultural identities and economic and recreational opportunities based around historical use of and interaction with species or natural resources in many areas are at risk. Proactive management strategies, such as the use of projected stream temperatures to set priorities for fish conservation, can help reduce disruptions to tourist economies and recreation.""
Surely the history of the USA is continuous loss (change) of identity by communities. If hunting lodges move to higher altitudes does it matter? Would it just be a stimulus for their economy?
Many of the fears (eg more hurricanes) have not yet occurred which doesn't mean they won't but could be handled cheaply without the massive economic costs to changes to CO2 emissions. In fact current known problems with pollution are far more worrying; every fish contains some plastic, hormones and dangerous chemicals wrecking significant ecosystems. Bees becoming extinct would cost the world far more than almost any temperature rise.
There is a small but finite chance of a major world wide climate catastrophe and that is why we should be acting now - this report summary will not inspire the international effort needed now.

Let me guess, November will be the “hottest on record.” You’ve got to love the entertainment value in it all..

The National Climate Assessment released its fourth report on climate change. According to the report, the Southern Great Plains - which includes Texas, Kansas, and Oklahoma - will be hit particularly hard by climate change.
Average temperatures will increase by 3.6–5.1 degrees Fahrenheit by 2050, and by 4.4–8.4 degrees Fahrenheit by the late 21st century.