Interviews And Articles by Nick Breeze
New research may well point to the fact that recent warming has produced more reliable vintages but if we look at some of the indicators of what the rest of this century really heralds then the forecast for many regions, including Britain, becomes much less rosy.
Retrospective analysis: 1600 - 2000
Looking back at 400 yrs of wine harvest records may seem like a longtime and certainly enough to base a study of viticulture on, however, we know that for the last ten thousand years we have been in a relatively stable climate period with a certain range of temperature variability that we have not strayed outside of. Whenever we have come close to the boundary of that variability, it has represented great hardships and often death for many people.
Scientists now tell us that we are leaving the stable ten thousand year period (called the ‘holocene’) and entering a new era driven by manmade climate, called the ‘anthropocene’. The great definer of this new epoch is the rising global mean temperature driven by the concentrations of greenhouse gases such as carbon dioxide, methane etc. that are the waste output from our industrial civilisation.
The Anthropocene: a new temperature epoch
Most of the reporting around this new paper on wine and climate change asserts that “if” temperatures continue to rise then there will be negative effects on viticulture. This “if” leaves the story somewhat open ended.
The scientific research that is looking at the rates of change and the projected temperature analysis point to dramatically higher temperatures. The IPCC have created what they call ‘Representative Concentration Pathways’ (RCP’s) which are scenarios that give an indication of temperature rise based on levels of CO2 emissions from human civilisation.
Chart showing IPCC 'Representative Concentration Pathways' (RCP's) and the current RCP of 8.5 that we are on
Currently we are on the highest and most dangerous RCP 8.5, with carbon emissions totalling around 40 billion tonnes each year. The recent news that global emissions actually stabilised in 2015 is terrific, but we still have to consider that CO2 is a long-lived greenhouse gas that takes over a thousand years to breakdown. This means that historic emissions give us a human contribution of about 1 trillion extra tonnes of greenhouse gases emitted from civilisation since the beginning of the industrial revolution.
We also have to add to this that the Earth’s climate takes a few decades to show signs of change as the huge carbon absorbing sinks, such as the world’s oceans and forests, are slow to respond at first, but once they pass a tipping point, are liable to flip from acting as a store of carbon, to being a carbon source.
Once this happens the rate of atmospheric carbon emitted is amplified from non-human sources and, like turning a thermostat up, the world heats much faster.
IPCC Scenario (SRES A2) for temperature rise by 2100
Interrelated change - a different set of ‘key performance indicators’
Climate model data showing projected temperature rise for the rest of this century are known to be conservative in their forecasts, as they don’t include many complex amplifying feedbacks that occur when one change in the Earth system (manmade or otherwise) sets off another.
For example, there is a huge threat of amplified warming from the loss of Arctic sea ice, caused when the reflective frozen white ice cap thaws and is replaced with dark heat absorbing ocean. Given the size of the Arctic ocean and it’s global position in relation to exposure to the sun, the potential for heat absorption is comparable alone to the warming caused by greenhouse gas emissions.
There is also a threat of methane release both on land and from the shallow ocean, already witnessed in the Arctic region, that will further accelerate global heating.
Another is sea-level rise, already conservatively estimated to be 1metre by the end of this century but, as I have been told by a leading glaciologist, it could be double that, or even as high as 4metres, we just don’t know.
Any global mean temperature rise over 2.5ºC has been shown by scientists to trigger a collapse of the planets forests. Dying forests mean more carbon released to the atmosphere, further amplifying warming, and also the end of one of our main sources of oxygen.
This graphic below clearly shows how global mean temperature over the last few decades has already shifted to a warmer world outside of the boundary of the natural distribution curve. To stop the temperature from continually rising there would need to be some countervailing force. Emissions reductions are often cited as being that countervailing force but they are just a step in the right direction, certainly not enough to stop temperatures rising in the succeeding decades.
As this distribution of summer temperature anomalies keeps moving to the right, the number of extreme weather events will continue to rise with a wide range of interrelated impacts. None of which will benefit wine growers or the rest of society at large.
Old world, new world - Growing wine in a vacuum
A rise in temperature, combined with even 1metre of sea-level rise would exacerbate the stresses that are already placed upon the interrelated system of human civilisation, from the global economy right down to our own individual prospects.
Despite such realities and the mounting evidence for what is occurring, it is always amazing to me that so many people in the wine world believe that viticulture will continue in a vacuum, barely scathed by the challenges that will engulf the rest of the world.
It is as if there is an idealised view that we’ll be popping corks of bubbly in Sussex, oblivious to food shortages due to the collapse in supply chains that will expose Britain’s shortfall and unpreparedness for what lies ahead.
This may all seem extreme but it is exactly the consequences we face from the trajectory of carbon emissions we have long ago set ourselves on. Those who say “we must cease emissions to stop global warming” conveniently forget the existing burden of 1 trillion tonnes of carbon that will continue to warm the planet over the succeeding decades (and centuries). Amplifying feedbacks are what many scientists fear we are close to, or perhaps are on the brink of triggering. Setting these in motion means temperature changes will be distinctly non-linear.
So I will end by reiterating one final point: analysing the last 400 years of wine harvest records maybe very interesting, but it would be wise to acknowledge that this time period represents less than 5% of a climatically stable period in the Earth’s recent history. The growing mass of climate data clearly show that the next 400 years will be nothing like it.
Nick Breeze has been interviewing climate scientists since 2010 and posting about wine since 2005. This article does not state viable human responses to climate change impacts because it is only intended as a response to the general reporting on the research paper, ‘Climate change decouples drought from early wine grape harvests in France’ published by Benjamin I. Cook & Elizabeth M. Wolkovich in the Nature Climate Journal, 2016. http://www.nature.com/nclimate/journal/vaop/ncurrent/full/nclimate2960.html
List of graphics / rich media:
1. Spratt - chart of holocene variability
2. Schellnhuber interview - ‘Anthropocene’
3. RCP’s relating to temperature rises
4. IPCC 2000 - 2100 temperature rise graphic (European)
5. Hansen’s recent demonstration of a shift in climate variability over recent decades
More posts by Nick Breeze
Subsea permafrost on East Siberian Arctic Shelf in accelerated decline
Interview by Nick Breeze with Dr Natalia Shakhova and Dr Igor Semiletov
A new scientific paper published in Nature Communication Journal demonstrates that the mechanisms of destabilisation of subsea permafrost, contrary to previous claims, provide new insights into increased emissions from the worlds largest deposits of methane, that exists in the East Siberian Arctic Shelf (ESAS).
The subsea permafrost has for thousands of years acted as a seal, restricting the flow of gas through the water column to the atmosphere. This paper clearly shows that permafrost degradation and the occurrence of gas migration pathways are key factors in controlling the emissions.
Does Figueres interview give clues as to why we went backwards from Copenhagen to Paris?
Comment: Watching our recent interview with Christiana Figueres, David Tattershall (Envisionation Limited) responded with considered concern with respect to her answer to the question on the reduction of emissions from the aviation industry.
Just to recap, here is the transcripted answer with Tattershall's response below:
Christiana Figueres: business must lead us to zero emissions
The lady who ushered in the Paris Agreement now wants to ramp up the pace and ensure the world reaches peak emissions by 2020, leading to total decarbonisation by 2050. The whole campaign hinges on the a new report that cites 2020 as a critical milestone for stemming the effects of climate change.
Christiana Figueres is persuasive and influential but in light of recent world events that include the destabilisation of the EU as a political block, and the openly anti-climate action administration of President Trump, it is very clear that the world has changed since Paris.
Lecture: Data analytics for climate decision-making
Centre for Science and Policy (CSaP): 2017 Climate Change Seminar Series
Science, politics, knowledge management, innovation and markets all play a role in climate change action, but what is the role of the University of Cambridge as an ‘anchor institution’ for these? Bringing together speakers spanning the worlds of research and policy, this series of events will explore how the multifaceted aspects of climate change action can come together to help us make the right decisions for the long run.
Why we need the Cambridge Climate Lecture Series
The window of opportunity is closing… but the price of failure is still too high!
The rate of ecological destruction is now so bad that the fate of our civilisation literally hangs in the balance. The loss of the Arctic polar ice cap, the melting from above and below of Antarctica, the culling and collapse of forests and dying oceans, failing ecosystems, our atmosphere burdened with hundreds of billions of tonnes of extra greenhouse gases, and still each week scientists report more broken links in the chains of interconnectedness that sustain each one of us, rich and poor, on this planet. Despite all this, the great human enterprise built on a foundation of carbon, rumbles on in search of new fixes.
Books: Polar Researcher says “A Farewell to Ice”
Peter Wadhams has achieved many accolades and held positions such as Director of the Scott Polar Institute in Cambridge Uk, among a great many others. He has been on more than 50 research trips to the polar regions and, of special interest to those studying the demise of the Arctic ice cap, he has been under the ice on 6 submarine expeditions.