Archive for the ‘Anthropocene’ Category
Tony Robinson is probably best known to most people (over the age of 40 at least) for playing the character of ‘Baldrick’, alongside Rowan Atkinson, in the Blackadder series of brilliant comedy series in the 1980s. However, since then, he has carved out a niche for himself presenting numerous Time Team programmes about archaeology. They are almost invariably excellent and the latest programme – all about a tsunami that hit the East coast of Britain about eight thousand years ago – was broadcast in the UK last night.
I am very pleased to discover that the broadcaster, Channel 4 Television, has uploaded the programme to YouTube and, therefore, I have embedded the video at the end of this post. I cannot recommend watching it highly enough but, if you need some encouragement, please allow me to summarise its content:
Tony Robinson open’s the programme from a helicopter above Flamborough Head in North Yorkshire and – in the course of the programme – visits places up and down the East Coast of England and Scotland. Using computer generated animation, the programme reveals that the tsunami was caused by an enormous underwater landslide on the edge of the continental shelf off the coast of Norway.
The programme also presents an amazing array of artefacts recovered from a site in North Yorkshire, called Star Carr, where peat has preserved all manner of objects – bone, wood, leather, etc – thereby painting a picture of a much more sophisticated and stable society in what is known, in anthropological terms, as the Mesolithic era.
With the help of experts, Robinson demonstrates how, unlike people in the Iron Age who tended (for reasons that will become clear) to live on hill-tops, people in the Mesolithic era lived next to rivers. Far from being hunter-gatherers, they lived in settled communities and, with the exception of fish, allowed their food to come to them. However, in terms of geography, the programme focussed on the fact, because sea level was much lower at the time, the UK was connected to Europe (from Denmark all the way round to Brittany in the northwest of France).
Probably the most fascinating artefacts presented in the programme are those that look very similar to things that, in modern times, early European explorers of Siberia found local Shamen using in their religious ceremonies. However, so as to encourage you to watch the video, I will not say any more than that!
So then, you may well be thinking, what has this got to do with concern for the environment and/or climate change? Well, having watched the programme, I was left feeling that Robinson had, to use a soccer-based analogy, dribbled the football up to an open goal and then, almost inexplicably, managed to fail to score a goal. It left me feeling that, although Robinson clearly accepts that the Earth’s climate has changed in the past, he does not believe that humans are the main driver of change today. If he did, he would not have closed the programme by suggesting that we might be heading for another Ice Age!
To me, this was completely at odds with all of the facts about palaeoclimatic changes presented in the programme:
— Sea Level was120m lower than it is today at the end of the last Ice Age (about 12k years ago).
— The tsunami probably resulted in a decision by humans not to live near sea level about 8k years ago.
— The sudden emptying of the enormous, North American, Lake Agassiz about the same time, which resulted in the UK being separated from Europe by the current expanses of water known as the North Sea and the English Channel.
I am quite sure that I cannot have been the only person to watch all this and think: “Holy Cow! We are already in an inter-glacial warm period and we are now moving into temperature conditions not seen since Antarctica first became glaciated in the Eocene era (35 million years ago)”. Therefore, although it may take hundreds of years, very significant sea level rise is now inevitable (because Eocene-like levels of atmospheric CO2 are now driving the Earth back towards Eocene-like temperatures).
As I said, the one conclusion I did not reach was: “Oh well, change happens. Ice Ages come and go and, if sea level drops again, travel to Europe will be much easier!”
Tony Robinson, yes, I am talking to you now! You seriously need to wake up! There will never be another Ice Age unless or until humans become extinct. Even if the Earth was to suddenly start to cool down (i.e. because we now understand why it has happened repeatedly in the past million years this is not expected to happen for many thousands of years), if humans were lucky enough to still be around, all they would have to do to stop this happening is release some of the CO2 they had managed to remove from the atmosphere (and buried underground like nuclear waste).
Despite my frustration at all of this, I would, as I said, heartily recommend that you invest the time in watching the video.
Last year, James Hansen (et al), pointed out that extreme weather events of all kinds (hot, cold, wet and dry) are becoming more frequent. In fact, their statistical analysis of historical data (as opposed to computer modelling of future events) demonstrated that extreme events (i.e. more than 3 standard deviation above or below average) are now ten times more likely than they used to be. As the authors put it:
We illustrate variability of seasonal temperature in units of standard deviation (σ), including comparison with the normal distribution (“bell curve”) that the lay public may appreciate. The probability distribution (frequency of occurrence) of local summer-mean temperature anomalies was close to the normal distribution in the 1950s, 1960s and 1970s in both hemispheres (Fig. 2). However, in each subsequent decade the distribution shifted toward more positive anomalies, with the positive tail (hot outliers) of the distribution shifting the most.
Last year it was the USA and Australia, today it is India that is suffering from a heatwave, with temperatures approaching 50C. Above 50C/120F, in dry air, proteins begin to break down (and plants die). Furthermore, a Wet Bulb temperature of 35C (which causes animals to die because they overheat) is reached at 40% relative humidity.
So much for global warming being beneficial.
If, like me until recently, you struggle with all this meteorological stuff, here is a nice graph from Wikipedia that tells you all you need to know about Wet and Dry Bulb temperatures and Relative Humidity.
I know this chart is complicated but, the important bit is the pale blue line with a “35” next to it. The top right corner of the graph (beyond this line) is therefore what you could call the “death zone” and the higher the Dry Bulb temperature (vertical lines in green) the lower the Relative Humidity (curves in red) required to enter it.
Words are not really necessary to accompany this image but, if you want some, feel free to go and read ‘The Last Time CO2 Was This High Humans Did Not Exist” by Andrew Freedman on the Climate Central website.
However, what I would really like to know is how anyone could possibly think that, since the Industrial Revolution, the Earth’s climate would not have been impacted by:
– a sevenfold increase in the the human population;
– a similar increase in the number of methane-producing livestock;
– a super-exponential increase in the burning of fossil fuels.
Therefore, those who still dispute the reality of anthropogenic climate disruption have not only picked a fight with history; they have picked a fight with science – the Laws of Conservation of Energy and Mass and the concept of Entropy in particular. Defeat is therefore inevitable. The only question that remains is how bad do things have to get before they are willing to admit they are wrong?
I am afraid this may be the last post on this blog for a while because – what with the all the willful blindness and ideological prejudice that seems to stop people from recognising what an Eff-ing mess humanity is in – and my as yet unresolved employment situation – I am feeling somewhat emotionally drained. However, please don’t cancel your subscription (as who knows how quickly I may recover).
Addendum (10:00 hrs BST 4 May 2013)
I would also recommend that reader take a look at this excellent post, ‘The “hockey stick” slaps back’, on the Skepticblog website. This takes readers on a journey back in time, looking at all the palaeoclimatic reconstructions that have been done for the last million years. Somehow, I managed to be the first person to post a comment on this piece, which reads as follows:
Why not go back even further by looking at sea floor sediments too? As in, for example, Zachos et al. (2001), ‘Trends, Rhythms, and Aberrations in Global Climate 65 Ma to Present’, Science 292: 686-93.
For those that are really interested, you can get a PDF of the whole paper here. It includes many fascinating diagrams, but one of the more complicated ones has been helpfully simplified by James Hansen in his book, Storms of my Grandchildren. All the figures from the book are available here but, with regard to Zachos et al (2001), Figure 18 is the one to which I refer. This too needs few words to convey its importance:
So said Lord (Julian) Hunt, Vice President of GLOBE and a former Director General of the UK’s Meteorological Office, in an article published in The Times newspaper on 2 April 2013 (behind paywall). Fortunately (for me and all those without a Times subscription), the text of what appears to be the same article has been released to the media by the British Embassy in Beijing. This is presumably because Lord Hunt refers to China.
However, without further comment from me, here is the article in full:
It was the chilliest Easter Day on record, and last month is the coldest March for at least 50 years. But we are not alone in shivering. Across much of Europe, temperatures have been unseasonably cold. In Germany, this has been called a once in a “100-year winter”.
We should not be surprised. It has long been expected that climate change would bring more weird or extreme weather — not just cold but rain, droughts and heat waves — to the UK. So longer spells of colder winter weather are consistent with this. As were drought conditions around this time last year, followed by many months of heavy rain which resulted in the UK experiencing in 2012, the second wettest year on record.
Extreme weather has become more frequent across the world. Australia started 2013 with a record breaking heat wave. Similarly, a heatwave in the US in 2012 (the warmest year on record for mainland America) contributed towards widespread drought which proved devastating for many crops. Russia also experienced its second warmest summer last year. This follows the country’s hottest summer on record in 2010 with states of emergency in seven Russian regions as a result of brush fires, while 28 other regions were put under states of emergency due to crop failures caused by drought.
And then there is the steady increase in peak rainfall rates. These have doubled in South East Asia,for instance over 30 years. It is such a problem that the Malaysians have built a huge SMART tunnel (or Stormwater Management And Road Tunnel) in Kuala Lumpur which doubles up as both a motorway and a six-mile long pipe to cope with flash floods. A similar less pronounced trend is occurring in the UK, which help explains the rise in localised, incredibly heavy showers which have brought flooding from Cumbria to Cornwall. This is caused by a change in the atmosphere called “vertical mixing” in which cumulus clouds become stronger and bigger.
In the UK, the trend is likely to be towards colder winters as a large part of Arctic ice melts permanently (as now happens every summer). The winds over the ice-free ocean could then push colder currents up to Iceland and the Arctic ocean. And as a result of colder waters from the North, the northern UK, in particular, may no longer enjoy the same level of warming from the Gulf Stream as it did when the sea ice boundary was further south.
It is these colder oceans which help to rebut one of the more common arguments used by sceptics to argue that “global warming has stopped”. They often point to graphs which purport to show that Earth’s temperature has not risen in 16 years. But that graph combines land and ocean temperature. Separate the two, and you see that on land temperature is still rising — 0.3℃ over the past decade. More dramatically, in China it has risen by 2℃ over the past 50 years, and 3℃ in the Antarctic over 30 years.
The drop in sea temperature is not just taking place in the Arctic, where the ice is melting, but equally strongly in the eastern Pacific, where winds off the South American coast bring deep, colder waters to the surface. Normally this La Niña phenomenon lasts for three to five years. However, it has been active for more than a decade, caused by easterly trade winds along the equator that have been strengthened by general warming of the atmosphere. When La Niña finally falls away, some time in the next few years, the surface cooling will end. This will increase temperatures over large areas of the globe, disrupting agriculture and fisheries in many countries, and pushing up food prices.
Fortunately, even some sceptics are won round when they experience the problems themselves. The scepticism of some Russian officials has disappeared as they have seen the permafrost melt in the north of the country, and watched the effects of prolonged heatwaves and droughts.
Responsible nations are preparing for the effects of climate change. However, all governments need constant encouragement, in the face of financial austerity and the claims of sceptics, to expand programmes to reduce greenhouse gas emissions.
It is critical they do so, otherwise future generations will have more to worry about than a freezing cold Easter Sunday.
For all those people who have not been duped into believing in the fallacy of the marketplace of ideas, Lord Hunt is someone whose opinions should carry weight. Experts are real and so is anthropogenic climate disruption. So, then, I really do hope that climate change denial will founder on the rocks of reality (and the sooner the better it will be for everybody).
What we know is this: As a whole (including the oceans), on average, over the long term, the Earth is getting warmer; and that it is doing so at a rate equivalent to – or in excess of – that at which it emerged from the last Ice Age. Therefore, since we were already in the middle of a warm inter-glacial period, the question remains, which one of these are we now witnessing:
ACD = Anthropogenic climate disruption; or
AGW = Anthropogenic Global Warming?
One is consistent with the reality that Earth’s climate is complicated (whereas the other is not). One is consistent with the fact that it can be unusually cold in one place whilst unusually hot somewhere else (whereas the other is not). One is consistent with the bulk of atmospheric physics; thermodynamics; and the Laws of conservation of Energy, Mass and Water (whereas the other is not).
Have you worked out which is which yet? If not, any or all of the following may help:
However, as highlighted by Joe Romm on the Think Progress website on 17 March 2013, it is not one that will always be true. With the author’s kind permission, this article, entitled ‘The Dangerous Myth That Climate Change Is Reversible’, is reproduced in full below.
If you have not already read it, I would very much recommend that you do so. However, by way of a summary, here are the key points as I see them:
1. The burning of fossil fuels is causing change that will not be reversible in any timescale meaningful to humans: Although the National Oceanic and Atmospheric Administration (NOAA) say this will be at least 1000 years, the Geological Society of London (GSL) has warned it could take at least 100 times longer than that to undo the damage we are now doing. That being the case, the longer we fail to address this issue the greater the likelihood that the GSL estimate will be correct.
2. Warming will only ever stop if total CO2 emissions are less than the rate of CO2 removal; and one is already twice the other. Any change (current and future) could only be reversed if the CO2 content of the atmosphere were to be reduced (i.e. if removal exceeds emissions). Artificial carbon capture and storage (CCS) is almost certainly impossible to achieve safely, at scale, and within the timescale required (to prevent unstoppable change). That being the case, change is effectively irreversible; and we must stop burning fossil fuels ASAP.
3. Wait and see is no longer a survivable option; we need to decarbonise our power generation systems as fast as possible. Burning all the Earth’s fossil fuels without CCS is very likely to cause unstoppable climate change (i.e. what is called a “runaway greenhouse effect” resulting from feedback mechanisms now observed to be mutually-reinforcing the change human activity has already caused).
Here, then, is Joe’s article in full:
The Dangerous Myth That Climate Change Is Reversible
The CMO (Chief Misinformation Officer) of the climate ignorati, Joe Nocera, has a new piece, “A Real Carbon Solution.” The biggest of its many errors comes in this line:
A reduction of carbon emissions from Chinese power plants would do far more to help reverse climate change than — dare I say it? — blocking the Keystone XL oil pipeline.
Memo to Nocera: As a NOAA-led paper explained 4 years ago, climate change is “largely irreversible for 1000 years.”
This notion that we can reverse climate change by cutting emissions is one of the most commonly held myths — and one of the most dangerous, as explained in this 2007 MIT study, “Understanding Public Complacency About Climate Change: Adults’ mental models of climate change violate conservation of matter.”
The fact is that, as RealClimate has explained, we would need “an immediate cut of around 60 to 70% globally and continued further cuts over time” merely to stabilize atmospheric concentrations of CO2 – and that would still leave us with a radiative imbalance that would lead to “an additional 0.3 to 0.8ºC warming over the 21st Century.” And that assumes no major carbon cycle feedbacks kick in, which seems highly unlikely.
We’d have to drop total global emissions to zero now and for the rest of the century just to lower concentrations enough to stop temperatures from rising. Again, even in this implausible scenario, we still aren’t talking about reversing climate change, just stopping it — or, more technically, stopping the temperature rise. The great ice sheets might well continue to disintegrate, albeit slowly.
This doesn’t mean climate change is unstoppable — only that we are stuck with whatever climate change we cause before we get desperate and go all WWII on emissions. That’s why delay is so dangerous and immoral. For instance, if we don’t act quickly, we are likely to be stuck with permanent Dust Bowls in the Southwest and around the globe. I’ll discuss the irreversibility myth further below the jump.
First, though, Nocera’s piece has many other pieces of misinformation. He leaves people with the impression that coal with carbon capture and storage (CCS) is a practical, affordable means of reducing emissions from existing power plants that will be available soon. In fact, most demonstration projects around the world have been shut down, the technology Nocera focuses on would not work on the vast majority of existing coal plants, and CCS is going to be incredibly expensive compared to other low-carbon technologies — see Harvard stunner: “Realistic” first-generation CCS costs a whopping $150 per ton of CO2 (20 cents per kWh)! And that’s in the unlikely event it proves to be practical, permanent, and verifiable (see “Feasibility, Permanence and Safety Issues Remain Unresolved”).
Heck, the guy who debated me on The Economist‘s website conceded things are going very slowly, writing “The idea is that CCS then becomes a commercial reality and begins to make deep cuts in emissions during the 2030s.” And he’s a CCS advocate!!
Of course, we simply don’t have until the 2030s to wait for deep cuts in emissions. No wonder people who misunderstand the irreversible nature of climate change, like Nocera, tend to be far more complacent about emissions reductions than those who understand climate science.
The point of Nocera’s piece seems to be to mock Bill McKibben for opposing the idea of using captured carbon for enhanced oil recovery (EOR): “his answer suggests that his crusade has blinded him to the real problem.”
It is Nocera who has been blinded. He explains in the piece:
Using carbon emissions to recover previously ungettable oil has the potential to unlock vast untapped American reserves. Last year, ExxonMobil reportedthat enhanced oil recovery would allow it to extend the life of a single oil field in West Texas by 20 years.
McKibben’s effort to stop the Keystone XL pipeline is based on the fact that we have to leave the vast majority of carbon in the ground. Sure, it wouldn’t matter if you built one coal CCS plant and used that for EOR. But we need a staggering amount of CCS, as Vaclav Smil explained in “Energy at the Crossroads“:
“Sequestering a mere 1/10 of today’s global CO2 emissions (less than 3 Gt CO2) would thus call for putting in place an industry that would have to force underground every year the volume of compressed gas larger than or (with higher compression) equal to the volume of crude oil extracted globally by [the] petroleum industry whose infrastructures and capacities have been put in place over a century of development. Needless to say, such a technical feat could not be accomplished within a single generation.”
D’oh! What precisely would be the point of “sequestering” all that CO2 to extract previously “ungettable oil” whose emissions, when burned, would just about equal the CO2 that you supposedly sequestered?
Remember, we have to get total global emissions of CO2 to near zero just to stop temperatures from continuing their inexorable march toward humanity’s self-destruction. And yes, this ain’t easy. But it is impossible if we don’t start slashing emissions soon and stop opening up vast new sources of carbon.
For those who are confused on this point, I recommend reading the entire MIT study, whose lead author is John Sterman. Here is the abstract:
Public attitudes about climate change reveal a contradiction. Surveys show most Americans believe climate change poses serious risks but also that reductions in greenhouse gas (GHG) emissions sufficient to stabilize atmospheric GHG concentrations or net radiative forcing can be deferred until there is greater evidence that climate change is harmful. US policymakers likewise argue it is prudent to wait and see whether climate change will cause substantial economic harm before undertaking policies to reduce emissions.Such wait-and-see policies erroneously presume climate change can be reversed quickly should harm become evident, underestimating substantial delays in the climate’s response to anthropogenic forcing. We report experiments with highly educated adults–graduate students at MIT–showing widespread misunderstanding of the fundamental stock and flow relationships, including mass balance principles, that lead to long response delays. GHG emissions are now about twice the rate of GHG removal from the atmosphere.
GHG concentrations will therefore continue to rise even if emissions fall, stabilizing only when emissions equal removal. In contrast, results show most subjects believe atmospheric GHG concentrations can be stabilized while emissions into the atmosphere continuously exceed the removal of GHGs from it. These beliefs-analogous to arguing a bathtub filled faster than it drains will never overflow-support wait-and-see policies but violate conservation of matter. Low public support for mitigation policies may be based more on misconceptions of climate dynamics than high discount rates or uncertainty about the risks of harmful climate change.
Again, zero emissions merely stops climate change, and obviously, thanks to fossil-fuel funded Tea Party politicians along with the deniers and the ignorati, we won’t be going to zero anytime soon.
Finally, I recommend RealClimate’s 2009 post, “Irreversible Does Not Mean Unstoppable“:
But you have to remember that the climate changes so far, both observed and committed to, are minor compared with the business-as-usual forecast for the end of the century. It’s further emissions we need to worry about. Climate change is like a ratchet, which we wind up by releasing CO2. Once we turn the crank, there’s no easy turning back to the natural climate. But we can still decide to stop turning the crank, and the sooner the better.
Indeed, we are only committed to about 2°C total warming so far, which is a probably manageable — and even more probably, if we did keep CO2 concentrations from peaking below 450 ppm, the small amount of CO2 we are likely to be able to remove from the atmosphere this century could well take us below the danger zone.
But if we don’t reverse emissions trends soon, we will at least double and probably triple that temperature rise, most likely negating any practical strategy to undo the impacts for hundreds of years.
With my thanks once again to Joe Romm, for permission to republish the above, all that remains for me now is to wish you all a pleasant [Passover/Easter/Spring Equinox] festival of renewal!