Why has global warming stalled?

BBC News, David Shukman, Science editor, 22 July 2013

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With Britain's heatwave reaching a peak, there could be no better moment to talk about why global warming has slowed to a standstill.

It reminds me of reporting on a drought a few years ago: while filming interviews with people about the impact, the heavens opened and rainwater was soon flowing down my neck.

So as journalists were invited to the Science Media Centre in London to hear how the worldwide rise in temperatures has stalled, the mercury shot up as if on cue to record the hottest day of the year so far.

In many ways, this event was long overdue: climate sceptics have for years pointed out that the world is not warming as rapidly as once forecast.

A lot depends on how you do the measurements, of course.

Each of the last few decades has been warmer than the last. But start your graph in 1998 - which happened to be an exceptionally warm year - and there hasn't been much global warming at all.

Gradually the words 'pause' and 'hiatus' which first featured in the blogs have crossed to the media and then to the scientists professionally engaged in researching the global climate.

The headline - which the scientists will not thank me for - is that no one is really sure why the rate of warming has stumbled.

No smoking gun

There are plenty of possible explanations but none of them adds up to a definitive smoking gun.

Industrialisation may lead to a drop in global temperatures in the 1940s

Professor Piers Forster of Leeds University has tried to quantify the different factors involved - what's known as their "radiative forcing".

Between 1998-2012, he reckons, manmade greenhouse gases were still the biggest influence, causing warming of 0.48 of a Watt per square metre (a key measure of energy flows to and from the planet).

At the same, he estimates, two other natural influences might have led to some cooling: a relatively quiet Sun might have been responsible for a reduction of 0.16 of a Watt/sq m and volcanic eruptions another 0.06 Watt/sq m.

A big unknown is the effect of aerosols - tiny particles released by industrial pollution which could cause a further cooling effect.

It is thought that the world's massive industrialisation after World War Two contributed to a slight drop in global temperatures in the late 1940s.

But the key factor - according to all the speakers at the briefing - is that whatever solar energy is making it through to the surface, much is being absorbed by the hidden depths of the oceans.

The Argo network of automated monitors has been deployed since 2005 to measure the waters as deep as 1,800m. This isn't a very long period but the data are apparently showing some warming - even in this short time frame.

And readings from satellites since 2000 show how much energy is arriving at the planet, and how much is leaving, so if the energy left behind is not manifesting itself in rising surface temperatures, then it must be going somewhere - and the deep ocean is the most plausible explanation.

Pauses expected

On top of that, the scientists say, pauses in warming were always to be expected. This is new - at least to me.

It is common sense that climate change would not happen in a neat, linear away but instead in fits and starts.

But I've never heard leading researchers mention the possibility before.

Arctic sea ice levels have fallen

Professor Rowan Sutton, of Reading University, said computer simulations or models of possible future climate scenarios often show periods of ten years with no warming trend - some even show pauses of 20-25 years.

And Professor Stephen Belcher, head of the Met Office Hadley Centre, said observations and models showed that on average there were - or would be - two pauses in warming every century.

I asked why this had not come up in earlier presentations. No one really had an answer, except to say that this "message" about pauses had not been communicated widely.

So where does this leave us, as greenhouse gases emissions keep rising but the temperature does not?

Dr Peter Stott, of the Met Office, pointed out that 12 of the 14 warmest years have occurred since the year 2000 and says that other indicators - like the decline in Arctic sea ice of 12.9% per decade and losses of snow cover and glaciers - still point to a process of manmade warming.

Bad maths

But what about another possibility - that the calculations are wrong?

What if the climate models - which are the very basis for all discussions of what to do about global warming - exaggerate the sensitivity of the climate to rising carbon dioxide?

Dr Stott conceded that the projections showing the most rapid warming now look less likely, given recent observations, but that others remain largely unchanged.

A Met Office briefing document, released at the briefing, says that, even allowing for the temperatures of the last decade, the most likely warming scenario is only reduced by 10% - so "the warming that we might have expected by 2050 would be delayed by only a few years".

Overall, it concludes, the pause "does not materially alter the risks of substantial warming of the Earth by the end of this century."

In other words, global warming is still on.

But until the pause can be properly explained, many people will take a lot of convincing - especially if the pause lasts longer than expected.

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THE RELATIONSHIP TO GAIA - April 2010 (Kryon channelled by Lee Carroll)

New Mini Ice Age

"The weather you have today, and all the alarming attributes of it, is a scenario of what was scheduled to happen on Earth anyway. I review again that the weather changes you are seeing prophesied by myself, 21 years ago, are not a surprise. The changes are not caused by the pollutants you put in the air. You call it global warming and that's a nice phrase, and perhaps that will get you to put less pollutants in the air – a very good thing. But what you are seeing in the weather shift today was not caused by Humans putting things into the air. It would have happened anyway in about 300 years."

"We've called this process the water cycle, since it's all about water, not about air. The water is the predominant attribute of Gaia and of the weather cycle you're seeing. More predominant is the temperature of it. The cycle is ice to water and water to ice, and has been repeated on this planet over and over and over. It is not new. It is not exceptional. It is not frightening. But it's a cycle that modern humanity has not seen before, and it's a long cycle that is beyond the life span of a Human Being. Therefore, it tends to be overlooked or not seen at all !"

"In the days of the Lemurians, the water level of the Pacific Ocean was almost 400 feet lower, and that's only 50,000 years ago. [Kryon invites science to check this out – the water level at that time.] That was a water cycle working, and the reason it was lower was due to so much of the water being stored as ice. Today you're going through another water cycle that will eventually lead to cooling. The last one was in the 1400s."

"Science sees that at about 1650. As mentioned, they are so slow there is no remembrance that a Human has of them except in past writings and in the rings of the trees. The time span of the changes is so great that environmental record keeping does not exist in the form that it does today. But you can still look at the rings of the trees and at the striations of the rocks and can generally figure out that a few hundred years ago, you had a mini-ice age. Now you're going to have another one." 

“2011 and Beyond” - What you are seeing, and why - Jan 16, 2010 (Kryon channeled by Lee Carroll) (Text version)

“… So now we've refreshed that which we have said before, a review. You are in the middle of a cycle that will bring cooling to the planet. It is not a heat cycle, but rather a cooling cycle. But it always starts with a short heat cycle. It has been here before. It will come again. It is a long cycle - one generation plus five years. That's how long it's going to last. It starts with the melting of the ice caps, which is far more than any of you have seen in your lifetime or those of your ancestors. It is a cycle whose repetition is thousands of years long, but one that has not yet been recorded to the books of Human record. But it's definitely been recorded in the cores of the ice and in the rings of the trees.

Thousands of years old, it is, and it happens in a cyclical way. It's about water. It starts with that which is the melting of the ice caps to a particular degree, which has a profound effect on the planet in all ways. You can't have that happen without seeing life change as well as Gaia change and you've seeing it already. What happens when you take that which is heavy on the poles [ice] and you melt it? It then becomes cold water added to that which is a very, very gentle and finite balance of temperature in the seas of the planet (1). The first thing that happens is a redistribution of the weight of water on the thin crust of the earth from ice at the poles to new water in the seas. The results become earthquakes and volcanoes, and you're seeing them, aren't you? You are having earthquakes in places that are not supposed to have earthquakes. Volcanoes are coming to life in a way that you've not seen before on a regular basis. There will be more. Expect them.

Is it too much to ask of a Human Being that if you live by a volcano that you know might erupt, maybe you ought to move? Yet there will be those who say, "It hasn't erupted in my lifetime or my parents' lifetime or my grandparents' lifetime; therefore, it won't." You may have a surprise, for all things are changing. That is what is happening to Gaia. ….“

"Recalibration of Knowledge" – Jan 14, 2012 (Kryon channelled by Lee Carroll) - (Subjects: Channelling, God-Creator, Benevolent Design, New Energy, Shift of Human Consciousness, (Old) Souls, Reincarnation, Gaia, Old Energies (Africa,Terrorists, Cuba, Iran, North Korea, Venezuela ... ), Weather, Rejuvenation, Akash, Nicolas Tesla / Einstein, Cold Fusion, Magnetics, Lemuria, Atomic Structure (Electrons, Particles, Polarity, Self Balancing, Magnetism, Higgs Boson), Entanglement, "Life is necessary for a Universe to exist and not the other way around", DNA, Humans (Baby getting ready, First Breath, Stem Cells, Embryonic Stem Cells, Rejuvenation), Global Unity, ... etc.) - (Text Version) 

"...The Weather... Again

My partner has been "against the grain" in the past years, giving you what I have channelled about the weather. Is it global warming? No. Is it going to get better? No. This is a two-generation cycle. There will continue to be earthquakes, tsunamis, volcanoes, and storms. This is a recalibration of life in the ocean, and humanity must go through this in any way they can. This is a cycle, a known and expected one, but since you haven't gone through it in modern times, it's not well understood yet. ..."