Month: September 2014

Reflections on the UN Climate Summit in New York

By Dr Simon Buckle,  Grantham Institute

“Once more unto the breach, dear friends, once more”

New YorkClimate change was not, so far as I know, one of the issues that Shakespeare wrote about, despite plays like “The Tempest” or (for the sceptically minded) “Much Ado about Nothing”.  But King Henry V’s lines in Act III of the play of that name could have been written for the UN Secretary General to deliver at the Climate Summit in New York on 23 September where, with the help of a VIP cast, he in effect also urged us to “stiffen the sinews” to address one of the defining issues of our age.  And he was right to do so.

Without concerted and sustained action to reduce greenhouse gas emissions from the major emitting economies and across various sectors, climate risks will continue to grow to potentially catastrophic levels.  Thirteen of the 14 warmest years on record have occurred during the 21st Century. Atmospheric concentrations of carbon dioxide are growing rapidly.  And on current trends, the average surface temperature of the planet is likely to be some 4 degrees Celsius warmer by the end of the century.

There is increasing evidence that action on climate change is compatible with continued economic growth and development. Indeed, one could argue that it is a prerequisite.  The recent Calderon report illustrates that in many cases action makes sense even in narrow economic terms and highlights the opportunities for action on cities, land use and energy.  While undoubtedly there will be losers as well as winners from a transition to a low-carbon economy, this fact has always been true of the major economic and social transformations that have shaped our world.

The point is that, unless we act, there is a real risk that humankind will face a far worse future than its recent past.  Financial investors see these risks – that’s why global investors representing US$24 trillion of assets have just called on “governments to develop an ambitious global agreement on climate change by the end of 2015. This would give investors the confidence to support and accelerate the investments in low carbon technologies, in energy efficiency and in climate change adaptation.”

I must admit, the analogy with Henry V is not perfect for (at least) two reasons.  First, the venue for the 2015 climate summit that is meant to finalise this new global agreement is Paris. Some six hundred years after the famous battle at Agincourt, I hope preparations for the summit will be marked by excellent co-operation between the UK and France, at all levels!

Second, an all out fight between the developed and the developing world must be avoided.  Clearly, whatever agreement is reached in Paris will have to address the diversity of nations and developing country concerns about finance and technology.  But the scale of the problem is now such that there can be no rigid divide between the developed and the developing worlds.  We will all have to work together if we are to achieve the peak in global emissions in the next ten to fifteen years or so, which is the first necessary step in reducing climate risks.

An international agreement between governments on its own will not be sufficient however.  Action needs to be taken at all levels – city, sub-national, national and regional – and across sectors.  To quote from the Calderon report, this will only happen if governments provide “consistent, credible, long-term policy signals”.  Well-designed policies can drive resource efficiency, create the conditions for investments in low-carbon, resilient infrastructure and stimulate innovation in the technologies we need and the new business models and social practices that will drive this generational transformation to a low-carbon world.

“Once more unto the breach, dear friends, once more”…

Feasibility and affordability of reducing greenhouse gas emissions

By Ajay Gambhir, Research fellow on mitigation policy at the Grantham Institute

wind turbines300The United Nations Climate Summit 2014, to be held in New York on 23rd September, comes at an important point in the calendar for discussions on how to address climate change. Next year will see nations submit pledges on their future greenhouse gas emissions levels, as part of the United Nations process culminating in the 21st Conference of the Parties (COP) in Paris at the end of 2015, the ambition of which is to secure a global agreement to tackle climate change.

There is now a rich body of evidence on the implications of mitigation at the global, regional and national levels. This note presents some of the evidence, revealed by research in the Grantham Institute over recent years, which supports the view that mitigation remains feasible and affordable.

Technologies and costs of a global low-carbon pathway

The Grantham Institute, in partnership with Imperial College’s Energy Futures Laboratory (EFL) demonstrated a relatively simple, transparent analysis of the relative costs of a low-carbon versus carbon-intensive global energy system in 2050. The report concluded that mitigation in line with a 2 degrees Celsius limit to global warming would cost less than 1% of global GDP by 2050 (excluding any potentially significant co-benefits from improved air quality and enhanced energy security).

Joint Grantham and EFL report: Halving global CO2 by 2050: Technologies and Costs

The importance of India and China

The two most populous nations, India and China, have undergone rapid economic growth in recent decades, resulting in significantly increased demand for fossil fuels, with associated increases in their CO2 emissions. Mapping pathways towards a low-carbon future for both regions presents challenges in terms of technology choices, affordability and the interplay with land, water and other resources. The Grantham Institute, in partnership with other research groups (including IIASA and UCL), has produced long-term visions of both regions using energy technology modelling and detailed technology and resource assessments, to set out pathways to very low-carbon economies which can be achieved at relatively modest costs. In addition, the Institute has undertaken assessments of the feasibility and cost of achieving the regions’ near-term (2020) Cancun pledges.

Grantham Report 1: An assessment of China’s 2020 carbon intensity target

Grantham Report 2: China’s energy technologies to 2050

Grantham Report 4: An assessment of India’s 2020 carbon intensity target

Grantham Report 5: India’s CO2 emissions pathways to 2050

Key sectors and technologies

Reports have been produced on a number of key technologies across all economic sectors and on the role that these can play in a low-carbon world: electric and other low-carbon vehicles in the transport sector; low-carbon residential heating technologies; other building efficiency and low-carbon options; and a range of technologies and measures to reduce emissions from industrial manufacturing.

The successful development and deployment of a range of low-carbon power sector technologies will be central to decarbonising the power generation sector over the coming decades, thereby providing the basis for low-carbon electrification in the building, transport and industrial sectors. The Institute has produced briefing papers on the technological status, economics and policies to promote solar photovoltaics and carbon capture and storage (including with bioenergy to produce net negative emissions).

Grantham briefing paper 2: Road transport technology and climate change mitigation

Grantham briefing paper 3: Carbon capture technology: future fossil fuel use and mitigating climate change

Grantham briefing paper 4: Carbon dioxide storage

Grantham briefing paper 6: Low carbon residential heating

Grantham briefing paper 7: Reducing CO2 emissions from heavy industry: a review of technologies and considerations for policy makers

Grantham briefing paper 8: Negative emissions technologies

Grantham briefing paper 10: Shale gas and climate change

Grantham briefing paper 11: Solar Power for CO2 mitigation

Grantham Report 3: Reduction of carbon dioxide emissions in the global building sector to 2050

Competitiveness

A critical consideration in any nation or region’s mitigation strategy is the degree to which a low-carbon transition might put its industries at risk of losing competitiveness against rivals in regions with less stringent mitigation action. In a landmark study using responses from hundreds of manufacturing industries across the European Union, researchers at the Institute, in partnership with the Imperial College Business School and Universidad Carlos III de Madrid, have produced robust evidence to support the contention that the EU’s Emissions Trading System has not produced any significant competitiveness impacts or industry relocation risks.

On the empirical content of carbon leakage criteria in the EU Emissions Trading Scheme – Ecological Economics (2014)

Industry Compensation under Relocation Risk: A Firm-Level Analysis of the EU Emissions Trading Scheme – American Economic Review (2014)

Global energy governance reform

The energy policies of governments around the world will, to a large extent, determine global greenhouse gas emissions.   Western governments cooperate on their energy policies through the International Energy Agency (IEA), which is a powerful advocate and analyst of low carbon energy strategies.  Unfortunately the IEA excludes developing nations, such as China, India, Brazil, Indonesia, from its membership.  The Grantham Institute is working with China’s Energy research Institute (ERI) to advise the Chinese government on China’s options for greater engagement in international energy cooperation, including closer association with the IEA.   China’s participation is important for world energy security and affordability – the other main objectives of energy policy –   as well as for climate mitigation.   A consultation draft report published by this ERI/Grantham project is at Global energy governance reform and China’s participation. An earlier report by the Grantham Institute with Chatham House is at Global energy governance reform.

Ocean heat uptake – checking the facts

The Climate and Environment at Imperial blog has moved. View this post on our new blog 

By Dr Flora Whitmarsh, Grantham Institute

The recent slowdown in global temperature rise has led to suggestions that global warming has stopped. In fact, the Earth system is still gaining heat, and the slowdown was likely caused by a series of small volcanic eruptions, a downward trend in the solar cycle, and increased heat uptake of the ocean. Writing in the Telegraph, Christopher Booker claims that a new paper by Professor Carl Wunsch (Wunsch, 2014) shows that ocean warming cannot explain the slowdown because the deeper ocean is in fact cooling rather than warming. Booker is incorrect in his interpretation of the paper, as Professor Wunsch explained in a letter of response to the Telegraph editor that was not published. Wunsch also wrote a letter to the editor of The Australian following a similarly misleading article in that newspaper. There are two threads to Christopher Booker’s argument in the Telegraph article. First, he suggests that the new paper refutes the idea that the pause is caused by an increase in ocean heat uptake, an interpretation that is untrue. Second, Booker gives a misleading interpretation of Wunsch’s appearance on the 2007 television documentary The Great Global warming Swindle in which Wunsch’s views were misrepresented by the documentary makers. Below, I describe the significance of ocean heat uptake and then discuss Booker’s two points in turn.

Figure 1
Figure 1: the amount of heat taken up by the upper ocean (above 700 m), deep ocean (below 700 m), atmosphere and earth, and the amount going into melting ice (IPCC, 2013).

   The significance of ocean heat uptake

The ocean is an important heat sink and has taken up over 90% of the extra heat absorbed by the Earth system over the last century. There is natural variation in the amount of heat being taken up by the ocean. This is part of the reason why the observed increase in surface temperatures has not been uniform in the past. All studies including this latest one agree that the ocean above 2000 m is absorbing a significant amount of heat and this is the main focus of studies trying to detect and attribute global warming. The study of the ocean below 2000m is interesting from a scientific point of view but is less relevant to the study of climate change because it takes a very long time for heat to mix to these lower layers. Heat is transferred to the deep ocean by the movement of water masses – the mixing driven by the small-scale movement of water molecules is too slow to be of much significance. Due to the locations of the major ocean currents, parts of the deep ocean such as the western Atlantic and the Southern Ocean in the Antarctic have been in contact with the surface relatively recently, meaning they would be expected to have warmed due to global warming. By contrast, much of the Pacific Ocean below 1500 m has not been in contact with the surface for around a thousand years – something that has been demonstrated by studying the radioactive decay of carbon-14 atoms  in a technique similar to the carbon dating of objects (Matsumoto, 2007 – see figure 2).

Figure 2
Figure 2: The circulation carbon-14 age of ocean water below 1500 m (Matsumoto, 2007). Much of the water in the deep Pacific Ocean has not been in contact with the surface for around 1000 years, meaning that its temperature is unlikely to have been influenced by human activities since the industrial revolution.

       What is happening in the deep ocean?

Christopher Booker writes, “Prof Carl Wunsch … has produced a paper suggesting not only that the warmists have no real evidence to support their claim other than computer modelling, but that the deeper levels of the oceans have, if anything, not been warming but cooling recently, thanks to climate changes dating back centuries.”

Figure 3
Figure 3: Change in ocean heat content between 1993 and 2011 below 2000 m depth, in units of 108 Joules. There has been heating at this level in the Western Atlantic and Southern Ocean and cooling elsewhere.

In the paper under discussion, Bidecadal Thermal Changes in the Abyssal Ocean, Wunsch looks at observations of ocean heat content. He found that the ocean as a whole and the top 700 m had gained heat since 1993, but that there had been an overall decline in heat content below 2000 m according to the available data. There has been a warming in the regions of the deep ocean below 2000 m where it would be expected due to the transport of water from the surface to the abyss by major ocean currents, i.e. the western Atlantic Ocean and the Southern Ocean (see figure 3). There was an observed cooling below 2000 m in other parts of the ocean including most of the Pacific. Much of the deep Pacific Ocean would not be expected to have warmed due to climate change because the water has not been in recent contact with the surface (figure 2). The available observations are very sparse and only about a third of the water below 2000 m was sampled at all during the period under discussion, meaning it is not known whether these results reflect a genuine cooling below 2000 m. Because there was heating in some places and cooling in others, it is particularly hard to accurately determine the mean from very sparse observations. The main conclusion of Wunsch, 2014 was in fact that more observations are needed to improve our understanding of processes involved in transporting water to the deep ocean. This is a subject which has received relatively little attention, with much more research effort being concentrated on the upper ocean. It is likely that this is partially due to the difficulty involved in observing the ocean at depth, and partly because the upper ocean is of interest due to its direct impact on weather patterns, for example through its role in the formation of El Niño and La Niña conditions. None of this changes the fact that the Earth system as whole is gaining heat, and that a significant proportion of that heat is being taken up by the ocean, mostly in the top 700 m. The paper doesn’t significantly change our understanding of the pause in surface temperature rise. We know that natural processes do change the amount of heat taken up by the ocean over time, and that surface temperature rise has not been uniform in the past. However, precisely quantifying how much heat has been taken up by the deep ocean is still not possible with current observations.

 

      The Great Global Warming Swindle

Referring to the 2007 television documentary, The Great Global Warming Swindle, Booker suggested that Wunsch had privately held “sceptic” views at the time the programme was aired, but didn’t feel able to express these views in public, “So anxious is the professor not to be seen as a “climate sceptic” that, [after being interviewed for] The Great Global Warming Swindle, he complained to Ofcom that, although he had said all those things he was shown as saying, he hadn’t been told that the programme would be dedicated to explaining the scientific case against global warming.” Professor Wunsch’s views on The Great Global Warming Swindle are explained at length on his professional webpage in an article dated March 2007. I will not paraphrase his comments in detail, but suffice it to say he states his belief that “climate change is real, a major threat, and almost surely has a major human-induced component”, and wrote to the documentary makers to say, “I am the one who was swindled” because they misrepresented his views by quoting him out of context. In an update written three months later, Wunsch made it clear that he did not complain to Ofcom under duress from other scientists. In fact, he felt so strongly that his opinions had been misrepresented that he filed his complaint despite threats by the documentary maker to sue him for libel. References Matsumoto, K. (2007), Radiocarbon-based circulation age of the world oceans, J. Geophys. Res., 112, C09004. Wunsch, 2014: Carl Wunsch and Patrick Heimbach, 2014: Bidecadal Thermal Changes in the Abyssal Ocean. J. Phys. Oceanogr., 44, 2013–2030.