[Green Growth:Korea's New Strategy (35)]World faces increasingly dire climate risks

The following is the 35th in a series of articles focusing on the Korean government`s "green growth" strategy. The series will also introduce the increasing efforts of major advanced countries of the world to promote a green economy. - Ed.

With the global community increasingly focusing its efforts on combating climate change, the question arises how imminent the dangers are. Some scholars believe the pace of global warming is actually accelerating at an alarming rate.

In an e-mail interview with The Korea Herald, Stanford University professor Christopher Field says sea levels may rise one meter or more by the year 2100, putting coastal cities at severe risk.

Field, who is a key author of the assessments issued by the United Nations` Intergovernmental Panel on Climate Change, asserts that unless governments around the world act quickly on climate change initiatives, a vicious cycle of global warming may be irrevocable.

Korea Herald: You`ve warned that the rate of climate change far exceeded previous estimations. How dire is the situation?

Chris Field: The real problem is that we don`t know how dire the situation is. What we do know is that the forcing of climate change, from the emission of heat-trapping gases by human activities, has grown very rapidly, so rapidly that we are now in a domain that has not been explored in detail using the most sophisticated climate models.

In addition, we have an increasing body of evidence pointing to the potential for strong "vicious cycle" feedbacks. These are processes with the potential to transfer additional greenhouse gases from the land or oceans to the atmosphere or to decrease the rate at which sinks on land or in the oceans remove carbon from the atmosphere. These vicious cycle feedbacks are not thoroughly understood. Based on work assessed by the IPCC, these feedbacks could increase global temperatures in 2100 by an additional 0.1 to 1.5 degrees. Other feedbacks not assessed by the IPCC could have effects in the same range, with a risk that is likely to increase as the amount of warming increases. The combination of strong forcing from high emissions plus vicious cycle feedbacks is exactly the direction we do not want to go.

In general, greenhouse gas emissions from human activity are closely connected with economic activity, and it is possible that we will see a decrease in emissions resulting from the global recession. The challenge for the future is that we need to find a way to decrease emissions while producing a vibrant global economy, hopefully one that creates opportunities for the people of all nations.

KH: Can you explain the term "feedback loops" and how this is speeding up the warming processes?

CF: A feedback loop is a cause and effect process where the effect influences (or feeds back on) the cause. If the change in the effect decreases the strength of the cause, then he feedback is negative or suppressive. A positive or vicious cycle feedback loop is one where a cause produces an effect that feeds back to increase the cause. A good example of a positive or vicious feedback cycle is the squeal that comes from placing a microphone too close to a speaker. Any little sound that gets picked up by the microphone comes out amplified through the speaker. The microphone picks up this amplified sound, which comes out of the speaker even louder, until the noise is so loud that somebody runs to move the microphone.

In the climate system, we get a positive or vicious cycle feedback when an increment of warming produces a change in the earth system that causes even more warming. For example, warming in snowy regions can cause the snow to melt earlier in the spring. When the snow is melted, the exposed plants and soil absorb more solar radiation, amplifying the warming.

Vicious cycle feedbacks driven through the carbon cycle can occur when warming causes the release of greenhouse gases, which amplify the warming. An example is that warming can cause thawing of frozen soils called permafrost. If these soils thaw, the organic matter they contain is susceptible to decomposition. Decomposition is the process, mediated by micro-organisms, that converts organic matter into carbon dioxide (the main greenhouse gas implicated in global warming) or methane (a greenhouse gas about 25 times as powerful as carbon dioxide).

Another example of a vicious cycle feedback loop involves forests. It is increasingly clear that global warming can increase the risk of wildfire. A wildfire is essentially the chemical process that converts the organic matter in plants into carbon dioxide.

KH: In essence, it seems you are describing a situation in which warming melts permafrost, releasing more carbon, resulting in more warming, and so on and so forth. Is this an irreversible cycle?

CF: At this point, we know the feedback from permafrost melting is a vicious cycle feedback, amplifying the warming, but we don`t know whether it is essentially a tipping point, where the process, once started, is essentially unstoppable. But we don`t know this for sure. It is also possible that a decrease or cessation of greenhouse gas emissions from human activity could partially or even completely halt the thawing of permafrost. Further research can help us constrain the probabilities. At this point, the cautious approach is to base our actions on the understanding that the risk is real.

KH: Protecting the tropical rainforests is a big concern. Does preventing rainforest deforestation supersede deforestation in the northern regions? Is deforestation of the north actually beneficial?

CF: Forests provide a wide range of benefits. They provide homes for vast numbers of plant and animal species. They hold the soil in place, help to clean water moving toward streams, and they remove pollutants from the air. In addition, the world`s forests (plants and soils) contain a quantity of carbon larger than that in the atmosphere. These features, plus the opportunities for recreation and spiritual renewal, provide strong motivations for placing a high priority on protecting forests and expanding forest areas.

When a forest dies, or when a forest is cut or burned, much of the carbon in its trees and soils is released to the atmosphere in carbon dioxide. This extra carbon dioxide tends to warm the climate. But forests can have additional effects on climate, beyond the effect related to greenhouse gas balance.

Specifically, forests are often darker in color than non-forest vegetation. This contrast in darkness, or in the fraction of the solar radiation that is absorbed, can be especially large in snowy regions, especially in the spring, when short vegetation is covered with reflective snow but a forest canopy is snow-free and dark.

In these snowy regions, forests help cool the planet by sequestering carbon, but they can help warm the planet by increasing the absorption of solar radiation. In general, the net effect of forests in these snowy regions is to warm the lowest level of the atmosphere, because the warming effect of the darker surface is larger than the cooling effect of the carbon storage.

Given all the benefits we receive from forests, I would never advocate cutting a forest in a snowy region to help fight global warming. But given the opportunity to protect a forest in the tropics or in a snowy region, I would tend to favor protecting the forest in the tropics. This is partly because protecting a forest in the tropics almost always helps fight global warming. But it is also partly because these forests provide such a broad set of crucial functions.

KH: Can you discuss the conflict of interest with promoting biofuel crops cultivation yet at the same time preserving our forests? Is there a happy medium?

CF: The management of agriculture to provide energy can be motivated by a number of considerations. Some stakeholders might be interested in offsetting the use of fossil fuels. Others might be interested in energy independence. Still others might be focused on improving the standard of living in rural communities.

In the public discussion of biomass energy in the last few years, much of the motivation has been on offsetting the use of fossil fuels. Biomass energy provides the possibility of offsetting fossil fuels, because plants grow by removing carbon dioxide from the air and converting it to plant using solar energy in the process called photosynthesis.

The combustion of the biomass (or the liquids derived from it) returns the carbon dioxide to the air. If no fossil fuels are required for the processing of the biomass energy, the net result of biofuel use on the atmosphere is no change in carbon dioxide. Photosynthesis removes carbon dioxide from the air and combustion returns it.

Managed carefully, biomass-based fuels can offset substantial amounts of fossil fuels at the same time they enhance energy security, and improve rural lifestyles. Managed carefully, biomass-based fuels can protect biodiversity and even increase soil carbon.

But achieving these benefits is not automatic. The potential problems with biomass-based fuels come from three issues. First, some approaches to making biomass-based fuels, especially the production of ethanol from corn grain, require an input of fossil-fuel energy that is nearly as large as the output of biomass-fuel energy. As a consequence, ethanol from corn provides little offset of fossil-fuel emissions.

Second, when biomass agriculture displaces food agriculture, there is a risk of greater food insecurity or higher food prices.

Third, if biomass crops are developed in areas not previously used for agriculture, clearing the existing vegetation can release large amounts of carbon dioxide to the atmosphere. This clearing essentially creates a carbon dioxide debt that needs to be repaid with fossil-fuel offsets from the biomass fuels grown in the site. Depending on the status of the pre-existing vegetation, the yield of the biomass crops, and the method used to extract energy from them, repaying this carbon debt may require decades or even centuries.

If the goal is managing the total amount of CO2 in the atmosphere, then it doesn`t really matter whether the CO2 comes from the combustion of fossil fuels or the clearing of a forest in order to plant biomass fuels. The only way to get a quick and lasting climate benefit of biomass fuel is to use land areas that don`t entail large CO2 releases for conversion to the biomass crop and to emphasize biomass fuels (often called second generation fuels) that do not require much input of fossil fuels for processing.

Without serious attention to the pre-existing vegetation and the fossil fuel requirement for producing the biomass fuel, biomass-based fuels provide little or no value in the fight against global warming.

KH: What are your recommendations in avoiding such a dire "worst-case" scenario with climate change.

CF: Personally, I am an optimist about the potential of the world community to deal effectively with climate change and to avoid the worst-case consequences. Success in this endeavor will, however, require great initiative, leadership, and dedication.

We need to make rapid progress in five important areas. I think of these as the four walls of the solution "house," plus an important floor. The four walls are conservation, efficiency, new technologies, and capture and storage.

Conservation is doing without the things we don`t really need - a good example is that we don`t really need to cut tropical forests in most places.

Efficiency is building better systems for transportation, residences, and manufacturing. It is saving energy by finding better ways to do the things we need to do.

New technologies refer to replacing the energy system based on fossil fuels with one based on non-carbon-based fuels - wind, solar, biomass, geothermal, tides, etc. I think we should also be looking at nuclear but deploying it only if we can assure ourselves of its safety.

Carbon capture and storage involves collecting the carbon dioxide from large fixed sources (basically power plants and factories) and injecting it into depleted oil formations or formations rich in salty water deep underground. The basic technology for carbon capture and storage is well developed through its use for enhanced oil recovery, but experience with applications motivated by CO2 storage goals is limited.

The floor under the solutions house is adaptation, responding effectively to the changes that can`t be avoided.

I see abundant opportunity for conservation, efficiency, new technologies, carbon capture and storage, and adaptation. Developing each of these approaches will, however, require major investments in technology development and learning by doing.

My concern is that people can look at the long-term potential of all these approaches and conclude that we need not act soon. My personal feeling, and this judgment is mine and not intended to represent the position of the IPCC, is that the exact opposite is true. We know we face serious issues with climate, and we know that addressing those issues will require major advances in technology, management, and planning. But I also personally feel that the need for progress represents a great opportunity, and that the leading companies or countries in coming decades will be those that take a leadership position in the technologies to decrease emissions of greenhouse gases from the combustion of fossil fuels.

Dealing effectively with the challenges of climate change will almost certainly not be simple or inexpensive. But the benefits of addressing climate change as quickly as possible will likely be vast. In addition to all of the benefits from developing new industries, early action minimizes the risk of vicious cycle feedbacks from melting sea-ice, thawing permafrost, and dying rainforests.

KH: As co-chair of a group at the IPCC, a plan is underway to draft a study that can serve as a guide to fighting climate-change disasters. Can you describe this project in more detail?

CF: The world`s nations formed the Intergovernmental Panel on Climate Change, a part of the U.N., to provide careful, comprehensive assessments of scientific knowledge concerning climate change. In a series of important reports since 1990, the IPCC has assessed the science of climate change, the impacts of climate change, possibilities for adapting to climate change, and strategies for minimizing the amount of change that occurs. The most recent full assessment of the IPCC was released in 2007, the same year that it shared the Nobel Peace Prize with Al Gore. Now, work on the next full report, scheduled for release in 2013 and 2014, is beginning. In the next month, the world`s nations will make a decision on whether to task the IPCC with a special assessment on the links between climate change, extreme events, and disasters. If there is a decision to proceed with this report, it will assess the role of climate change in altering disaster risks and it will evaluate strategies for adapting to these changes. If approved, the special report will likely be completed in 2011 or 2012.

KH: Which nations or areas are particularly vulnerable to natural disasters due to climate change? Are you receiving a lot of assistance from experts all over the globe?

CF: The 2007 report of the IPCC reached two very important conclusions about vulnerability to climate change. The first is that some regions are especially vulnerable. This includes regions where people are generally poor (especially Africa and Asia), and regions where the impacts of the climate changes will be profound (especially small, low-lying islands susceptible to sea-level rise and arctic regions susceptible to the large amount of warming they are projected to experience).

The second important conclusion is that there are vulnerable people, activities, and locations in every region. Often, these are the people who are vulnerable to other stresses - the elderly, the very young, the poor, and those with illnesses. The vulnerable activities vary from place to place. In some places, the vulnerable activities may involve agriculture or fisheries. In others, they may involve winter recreation. In still others, the vulnerable activities may be those most susceptible to wildfire. Vulnerable locations in a region may be those in places susceptible to drought, flooding, or heatwaves, or they may be those who live in the path of coastal storms.

The IPCC is a magnificent effort, involving input from essentially all of the world`s governments, plus the mostly volunteer efforts of thousands of leading scientists. I am not aware of another scientific issue where the world`s scientific community has been so dedicated to providing decision makers with the best available scientific information.

KH: Any final comments?

CF: Climate change is one of the most challenging, multidimensional, and important issues humanity has faced. Dealing effectively with the challenge of climate change will require the dedication, leadership, and creativity of all sectors of society - scientists, governments, the private sector, and individuals. In many ways, the world community is still in the early stages of dealing with climate change. Success will require both solid commitment and broad engagement. Personally, I think we can successfully avoid the most dire impacts of climate change, if we work together.

By Henry Shinn