Click on the headline (link) for the full text.
Many more articles are available through the Energy Bulletin homepage
Urgency and Global Warming: An Interview with Martin I. Hoffert
David Houle, Scientific Blogging
In this fifth installment of our on-going series of interviews with some of the leading thinkers and scientists on the subject of energy, we interview Martin Hoffert.
Martin I. Hoffert is Professor Emeritus of Physics and former Chair of the Department of Applied Science at New York University. He is a member of the American Geophysical Union (AGU), the American Institute of Aeronautics and Astronautics (AIAA) and was elected fellow of American Association for the Advancement of Science (AAAS). I met Marty at the Foundation for the Future’s Energy Conference a couple of months ago and was struck by his passionate outspokenness on the energy issues confronting the world today. Whether it was due to his emeritus stature, which allows him to speak without an institutional filter or just his nature, he was one of the most passionate and delightfully opinionated scientists at the conference. Enjoy the following interview with Marty.
Please note that at the end of the interview there are two links from YouTube that feature Marty. I strongly recommend that you watch them. they are enjoyable. One is from PBS and the other from CNN.
1. Scientificblogging.com: In your presentation at the Foundation for the Future’s “Energy Challenges: The Next Thousand Years” you were quite emphatic about the urgency for humanity to change energy consumption, and the types of energy that is used. Please elaborate and perhaps suggest timelines for this to occur.
Hoffert:Avoiding a planet-changing global warming catastrophe is why we urgently need to transform the global energy system to a carbon-neutral one. The clock is ticking. Absent the fossil fuel greenhouse this transformation could be deferred to the 22nd century or later.
There’s enough energy in coal (more than twice oil and gas combined) to run high-tech civilization a few hundred years more; enough for electric power generation by conventional pulverized coal plants; enough for coal-derived synthetic liquid fuel powered motor vehicles and aircraft. Unfortunately, there’s also enough carbon in this coal that burning it is likely to drive climate back a hundred million years, when atmospheric CO2 levels were 3-4 times higher, global temperatures 10 degrees Celsius hotter, sea level 100 meters higher and both poles deglaciated. Dinosaurs and crocodiles roamed the warm polar latitudes of this middle-Cretaceous Earth. We’re well on the path to planet-changing from what Roger Revelle and Hans Seuss called our “grand geophysical experiment:” the transfer of hundreds of billions of tons of carbon in fossil fuels to atmospheric CO2. It’s already started.
The good news is that three technology classes of carbon-neutral primary power in some combination could mitigate the worst impacts: (1) coal gasifiers driving integrated combined cycle power plants for electricity and hydrogen production with CO2 capture and storage in deep saline aquifers; (2) nuclear plants running on sufficiently abundant fissile fuels (i.e., U-233 bred from thorium) and eventually fusion; and (3) renewables, mainly solar and wind, along with appropriate transmission and storage technologies and smart, eventually global grids, perhaps superconducting, capable of matching electricity supply and demand load curves; and space solar power beaming energy collected in orbit to grid-interconnects worldwide for base load electricity.
(22 August 2007)
Recommended by JMG at Gristmill: One more scientist on the need for urgency.
Topsoil Loss – Causes, Effects, and Implications (Literature Review and Analysis)
Bruce Sundquist, personal site
– Soil Erosion Basics –
– Causes and Dynamics –
– Global Topsoil Loss –
– Erosion Data by Countries –
– Urbanization-Caused Topsoil Loss –
– Green Revolution, Fertilizers, Pesticides –
– Food Supply From Soils –
– Soil Conservation Laws and Politics –
– Soil Loss History and Economics –
From the general page:
This web site contains mainly a collection of five literature reviews done to understand the global magnitude of the degradation and loss of some of the earth’s key life-support systems:
Topsoil Loss – Causes, Effects and Implications: A Global Perspective
Forest Lands Degradation: A Global Perspective
Grazing Lands Degradation: A Global Perspective
Irrigated Lands Degradation: A Global Perspective
Fishery Degradation: A Global Perspective
…Even though this web site limits itself to categorized compilations of key facts and figures and brief summaries of arguments and analyses, the size of this site is equivalent to over 1000 pages of 8.5×11 hard copy (in 67 files). Yet it covers only a small fraction of the global literature on these issues. It is big enough to be quite useful, but you, the user, should keep the scope limitations of this site in mind. There are no graphics anywhere in this website since it is assumed that you are primarily interested in collecting referenced information as rapidly as possible.
(July 2007)
Tipping points in the Earth system
Timothy M. Lenton, Earth System Modelling Group University of East Anglia, Norwich UK
The Intergovernmental Panel on Climate Change (IPCC) in its many excellent reports tends to portray climate change as a smooth transition. Although the projections are rarely straight lines the underlying system and its responses appear ‘linear’ (in mathematical terms).
There are, of course, exceptions to this, notable ones being the possible collapse of the Atlantic thermohaline circulation or irreversible melt of the Greenland ice sheet, which both get significant attention in the latest IPCC report (IPCC, 2007). These represent large scale ‘non-linear’ components of the Earth system.
The apparent smoothness of typical IPCC projections presented arises for (at least) three reasons: (i) they tend to focus on global mean quantities (e.g. temperature, sea-level) that aggregate and average over regional scale spatial variability, (ii) these global average projections often come from a simple box model (MAGICC) that has been ‘trained’ to emulate large scale features of state-of-the-art general circulation models (GCMs) but not their non-linear and stochastic features, (iii) where GCM output is shown it is typically averaged over relatively long time windows, and sometimes over ensembles of runs, in order to iron out short-term temporal variability.
This is not to say that the overall response of the Earth system, full of non-linearity though it is, could not be smooth and quasi-linear. However, there are many components (or sub-systems) of the Earth system that could display non-linear behaviour and transitions under human (anthropogenic) climate forcing.
Such non-linear transitions where “a small change can make a big difference” have been described as ‘tipping points’ – a term popularised in a sociological context by Malcolm Gladwell in his book ‘The Tipping Point’. For clarity, we have recently introduced the term ‘tipping element’ to describe the components of the Earth system that can be switched – under particular conditions – into a qualitatively different state by small perturbations (Lenton et al, submitted).
The term ‘tipping point’ is then used to refer to the critical point (in forcing and a feature of the system) at which such a transition is triggered. This article will expand on the tipping elements in the Earth system that may be triggered by anthropogenic climate change, and where their tipping points may lie. It is based on research that began when a group of us (H. Held, H. J. Schellnhuber and I) organised a UK-German workshop on ‘Tipping points in the Earth system’ at the British Embassy, Berlin, 5-6 October 2005. An international expert elicitation exercise (led by E. Kriegler and J. Hall) was initiated at the workshop and continued through 2006 into 2007.
Meanwhile I undertook a comprehensive review of the literature related to tipping points. The results of the workshop, review and expert elicitation are currently under review with scientific journals (Lenton et al., submitted; Kriegler et al., submitted). Here I will give a summary and personal perspective.
(17 August 2007)
