News and Outreach: Kenneth Strzepek

June 13, 2013
Alli Gold
MIT Joint Program on the Science and Policy of Global Change

If you know how much something costs, you can budget and plan ahead. With this in mind, a team of researchers from MIT, the World Bank and the International Food Policy Research Institute recently developed a country-level method of estimating the impacts of climate change and the costs of adaptation. This new method models sector-wide and economy-wide estimates to help policymakers prepare and plan for the future.

"Previous country-level research assessing climate change impacts and adaptation either focused on economy-wide estimates or sector-by-sector analysis, without looking at the bigger picture," says Kenneth Strzepek, one of the lead authors of the study and a research scientist at MIT's Joint Program on the Science and Policy of Global Change. "By looking at the interplay between different sectors and within the economy, we are able to evaluate the indirect effects and interactions that can occur that are often not captured."

As a case study, the researchers apply their technique to Ethiopia — the second most populated country in Sub-Saharan Africa. They look at three key sectors: agriculture, road infrastructure and hydropower.

"These sectors were selected because of their strategic role in the country's current economic structure and its future development plans," Strzepek says.

Agriculture accounts for about 46 percent of the GDP in Ethiopia and is almost entirely rain-fed. Variability in temperature and rainfall will have major impacts on this crucial industry. The researchers found that with a temperature increase of two degrees Celsius, more intense drought and floods will cause a drop in crop production — triggering reductions in income, employment and investments.

Frequent and intense flooding will also damage Ethiopia's road infrastructure — the backbone of the country's transportation system and a needed link in the agricultural supply chain. The researchers found that flooding brought on by climate change will increase maintenance costs by as much as $14 million per year for the existing road network, which is expected to grow dramatically in the next 40 years.

The intense variability of precipitation will also greatly impact the country's hydropower and associated reservoir storage, which could provide energy, irrigation and flood mitigation. Because there is currently little installed hydro capacity in Ethiopia, the model showed few climate change impacts. But in the coming years, the government plans to invest heavily in this sector, meaning there could potentially be significant impacts to this sector as well.

Additionally, the researchers found that there would be an increased demand for water across sectors and create challenges for policymakers to effectively distribute this important resource. For example, Ethiopia plans to expand irrigated agriculture by 30 percent by 2050. The researchers found that some of the irrigation demands will be unmet, placing demands on other sectors requiring water resources.

"This research makes clear the impact droughts, floods, and other effects brought on by climate change can have on major financial sectors and infrastructure," Strzepek says. "For Ethiopia, we find that one of the best defenses against climate change is investment in infrastructure for transportation, energy and agriculture. By building up these sectors, the government will be able to enhance the country's resiliency."

He continued, "In predicting the outcomes of future water, infrastructure and agriculture projects, we were able to test the effectiveness of policies. This gives decision-makers in these countries, as well as international organizations, the information they need to continue to grow, develop and plan for the future with climate change in mind."

Planning for climate change is essential, Raffaello Cervigni, a co-author of the study and lead environmental economist at the World Bank, writes in a recent blog post.

"Addressing climate change is first and foremost a development priority for Africa … If no action is taken to adapt to climate change, it threatens to dissipate the gains made by many African countries in terms of economic growth and poverty reduction over the past ten years," he writes.

But, he continues, "a harsher climate need not be an impediment for Africa's development," if we can come together to address these challenges.

The integrated approach used by the authors is now being applied to studies on the costs of adapting to climate change in Ghana and Mozambique, as well as Vietnam. Others have replicated the approach to help other countries calculate the costs of adaptation.

Reprint 2013-7

By: Vicki Ekstrom

MIT researchers enhance model to assess the risks of water stress.

A conflict over water management has intensified along the Mississippi and Missouri rivers. Downstream states argue water should be released from the Missouri’s upstream reservoirs into the Mississippi to allow shipping to continue in the record low-level waters. Upstream states are fighting to keep the water to irrigate their crops and prevent the drought from getting even worse next year. To add to the tension, still others want to move a portion of the Missouri River Basin’s water to the Colorado Basin—which will see demand outstrip supply in the coming decades, according to a federal study released last week. 

These are the stakes in the conflict over water, and the impacts could be profound and widespread. Agriculture, river navigation, energy and other industries all stand to lose as populations increase and the possible side effects of climate change emerge. To measure future changes on water resources, researchers at the Massachusetts Institute of Technology have enhanced their global model to include a new tool that assesses the risks of water stress.

“As fresh water sources throughout the world experience considerable stress because of an increasing population, economic growth, and droughts, floods and other climate effects, this tool will provide valuable insights to industries and communities competing for water,” says Ken Strzepek, a researcher at the MIT Joint Program on the Science and Policy of Global Change, who helped design the tool.

Strzepek and his colleagues Adam Schlosser and Élodie Blanc take population, GDP and other socio-economic factors and combine them with hydro-climatic information such as precipitation and runoff from their earth system model. They then combine this information to estimate changes in demand across sectors such as public and private water use, agricultural use and thermoelectric cooling used in energy production. The result is an expanded model that can forecast if and where there could be stresses within water basins, along with the risks surrounding those changes.

“Globally, the tool is helping us see where the hot spots for water stress are and where might that stress increase in the future due to human growth and climate change—two factors that are coming together and exacerbating the problem of water management,” says Schlosser, the assistant director of science research at the Joint Program on Global Change.

While the new model paints the picture globally, it can also be applied at a regional and even local scale to help communities make important decisions about their future energy investments, infrastructure plans and adaptation strategies. Uniquely, by incorporating risk and uncertainty, the model helps policymakers evaluate the question: What investments do we need to make to be better prepared?

“When looking at different climate models, not only do they show different results, they show different directions—one shows a positive change where another might show a negative change,” Schlosser says. “However, our technique allows us to quantify this uncertainty as risk to help decision makers formulate more robust investment plans.”

The researchers have already begun to apply their model to the U.S. While their findings are still being written, the researchers agree that critical water management issues will arise—and in some areas are already emerging. They are finding that the areas that will see the greatest stress going forward are the same places where very rigid water management laws already exist, such as around the Missouri, Mississippi and Colorado rivers.

“Our model framework is able to account for water management and allocation policies,” Schlosser says. “This allows us to take a situation like transferring water from the Missouri to the Colorado Basin and assess the impacts to both basins going forward.”

Drawing from this measure of risk, the researchers warn that decision makers in developing countries should make their adaptation plans both flexible and efficient.

“If we don’t know how much water will come down the river, we should design dams to be constructed in stages. For example, we should make provisions to add hydropower generation capacity easily and accordingly. ” Strzepek says. “We need to have flexible designs, and also efficient designs, so we’re building in a way that the structure will perform well under a variety of climates.”

Read more about the new tool here.

The policy community has long prophesied about the coming water wars. But don't expect them anytime soon. More likely, tensions over access will merely exacerbate existing regional conflicts.

By: Shlomi Dinar, Lucia De Stefano, James Duncan, Kerstin Stahl, Kenneth M. Strzepek, Aaron T. Wolf

Right: Looking south over the Mediterranean and down the Nile, from the International Space Station. (NASA / flickr)


The world economic downturn and upheaval in the Arab world might grab headlines, but another big problem looms: environmental change. Along with extreme weather patterns, rising sea levels, and other natural hazards, global warming disrupts freshwater resource availability -- with immense social and political implications. Earlier this year, the Office of the Director of National Intelligence published a report, Global Water Security, assessing hydropolitics around the world. In it, the authors show that international water disputes will affect not only the security interests of riparian states, but also of the United States. 

In many parts of the world, freshwater is already a scarce resource. It constitutes only 2.5 percent of all available water on the planet. And only about .4 percent of that is easily accessible for human consumption. Of that tiny amount, a decreasing share is potable because of pollution and agricultural and industrial water use. All that would be bad enough, but many freshwater bodies are shared among two or more riparian states, complicating their management.

Of course, the policy community has long prophesied impending "water wars." In 2007, UN Secretary General Ban Ki Moon warned that "water scarcity ... is a potent fuel for wars and conflict." Yet history has not witnessed many. In fact, the only official war over water took place about 4,500 years ago. It was a conflict between the city-states of Lagash and Umma in modern day Iraq over the Tigris river. More recently, there have been some close calls, especially in the arid Middle East. About two years before the 1967 War, Israel and Syria exchanged fire over the Jordan River Basin, which both said the other was overusing. The limited armed clashes petered out, but the political dispute over the countries' shared water sources continues. In 2002, Lebanon constructed water pumps on one of the river's tributaries, which caused concern for downstream Israel. The project never provoked any formal military action, but with peace in the region already precarious, verbal exchanges between the two countries prompted the United States to step in. Both parties eventually accepted a compromise that would allow Lebanon to withdraw a predetermined amount of water for its domestic needs.

In short, predictions of a Water World War are overwrought. However, tensions over water usage can still exacerbate other existing regional conflicts. Climate change is expected to intensify droughts, floods, and other extreme weather conditions that jeopardize freshwater quantity and quality and therefore act as a threat-multiplier, making shaky regions shakier.

So what river basins constitute the biggest risks today? In a World Bank report we published in 2010 (as well as a subsequent article in a special issue of the Journal of Peace Research) we analyzed the physical effects of climate change on international rivers. We modeled the variability in river annual runoff in the past and for future climate scenarios. We also considered the existence and nature of the institutional capacity around river basins, in the form of international water treaties, to potentially deal with the effects of climate change.

According to our research, 24 of the world's 276 international river basins are already experiencing increased water variability. These 24 basins, which collectively serve about 332 million people, are at high risk of water related political tensions. The majority of the basins are located in northern and sub-Saharan Africa. A few others are located in the Middle East, south-central Asia, and South America. They include the Tafna (Algeria and Morocco), the Dasht (Iran and Pakistan), the Congo (Central Africa), Lake Chad (Central Africa), the Niger (Western Africa), the Nile (Northeastern Africa), and the Chira (Ecuador and Peru). There are no strong treaties governing the use of these water reserves in tense territories. Should conflicts break out, there are no good mechanisms in place for dealing with them.

By 2050, an additional 37 river basins, serving 83 million people, will be at high risk for feeding into political tensions. As is the case currently, a large portion of these are in Africa. But, unlike today, river basins within Central Asia, Eastern Europe, Central Europe, and Central America will also be at high risk within 40 years. Some of these include the Kura-Araks (Iran, Turkey, and the Caucasus), the Neman (Eastern Europe) Asi-Orontes (Lebanon, Syria, Turkey), and the Catatumbo Basins (Colombia and Venezuela).

CROSSING THE NILE

Among the larger African basins, the Nile has the greatest implications for regional and global security. Tensions over access to the river already pit Ethiopia and Egypt, two important Western allies, against one another. Egypt has been a major player in the Middle East Peace Process and Ethiopia is an important regional force in the Horn of Africa, currently aiding other African forces to battle Al-Shabbab in Somalia.

Over the years, a number of international water treaties have made rules for the basin, but they are largely limited to small stretches of it. In particular, only Egypt and Sudan are party to the 1959 Nile River Agreement, the principal treaty regarding the river. Egypt, which is the furthest downstream yet is one of the most powerful countries in the region, has been able to heavily influence the water-sharing regime. Upstream countries, such as Ethiopia and Burundi, have been left out, hard-pressed to harness the Nile for their own needs.

In 1999, with increasingly vitriolic rhetoric between Egypt and Ethiopia sidetracking regional development, the World Bank stepped up its involvement in the basin. It helped create a network of professional water managers as well as a set of investments in a number of sub-basins. Still, the drafting of a new agreement stalled: upstream countries would not compromise on their right to develop water infrastructure while downstream countries would not compromise on protecting their shares. In 2010, Ethiopia signed an agreement with a number of the other upstream countries hoping to balance against Egypt and Sudan. More recently, the country has also announced plans to construct a number of large upstream dams, which could affect the stability of the region.

By 2050, the environmental state of the Nile Basin will be even worse. That is why it is important to create a robust and equitable water treaty now. Such a treaty would focus on ways to harness the river's hydropower potential to satiate the energy needs of all the riparian states while maintaining ecosystem health. The construction of dams and reservoirs further upstream could likewise help even out water flows and facilitate agricultural growth. Projects such as these, mitigating damage to ecosystem health and local populations, would benefit all parties concerned and thus facilitate further basin-wide cooperation.

UP IN THE ARAL

Another water basin of concern is the Aral Sea, which is shared by Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, and Uzbekistan. The basin consists of two major rivers, the Syr Darya and Amu Darya. During the Soviet era, these two rivers were managed relatively effectively. The break-up of the Soviet Union, however, ended that. The major dispute now is between upstream Kyrgyzstan and downstream Uzbekistan over the Syr Darya. During the winter, Kyrgyzstan needs flowing water to produce hydroelectricity whereas Uzbekistan needs to store water to later irrigate cotton fields.

The countries have made several attempts to resolve the dispute. In particular, downstream Uzbekistan, which is rich in fuel and gas, has provided energy to Kyrgyzstan to compensate for keeping water in its large reservoirs until the cotton-growing season. Such barter agreements, however, have had limited success because they are easily manipulated. Downstream states might deliver less fuel during a rainy year, claiming they need less water from upstream reservoirs, and upstream states might deliver less water in retaliation. Kyrgyzstan, frustrated and desperate for energy in winter months, plans to build mega hydro-electric plants in its territory. And another upstream state, Tajikistan, is likewise considering hydro-electricity to satiate its own energy needs. Meanwhile, Uzbekistan is building large reservoirs.

Although these plans might make sense in the very near term, they are inefficient in the medium and long term because they don't solve the real needs of downstream states for large storage capacity to protect against water variability across time. In fact, both Kyrgyzstan and Uzbekistan, along with Kazakhstan, will see substantial increases in water variability between now and 2050. And so, the need to share the benefits of existing large-capacity upstream reservoirs and coordinate water uses through strong and more efficient inter-state agreements is unavoidable.

A stabilized Aral Sea basin would also benefit the United States. With its withdrawal from Afghanistan, Washington has been courting Uzbekistan as a potential alternative ally and provider of stability in the region. The Uzbek government seems willing to host U.S. military bases and work as a counter-weight to Russia. Kyrgyzstan is also an important regional player. The Manas Air Base, the U.S. military installation near Bishkek, is an important transit point. The country is also working with the United States to battle drug trafficking and infiltration of criminal and insurgent groups. Regional instability could disrupt any of these strategic relationships.

If the past is any indication, the world probably does not need to worry about impending water wars. But they must recognize how tensions over water can easily fuel larger conflicts and distract states from other important geopolitical and domestic priorities. Since formal inter-state institutions are key to alleviating tensions over shared resources, it would be wise, then, for the involved governments as well as the international community to negotiate sufficiently robust agreements to deal with impending environmental change. Otherwise, freshwater will only further frustrate stability efforts in the world's volatile regions.

SHLOMI DINAR is associate professor in the Department of Politics and International Relations and associate director of the School of International and Public Affairs at Florida International University. LUCIA DE STEFANO is associate professor at Complutense University of Madrid and researcher at the Water Observatory of the Botín Foundation. JAMES DUNCAN is consultant on natural resource governance and geography with the World Bank. KERSTIN STAHL is senior scientist at the Institute of Hydrology in the University of Freiburg. KENNETH M. STRZEPEK is research scientist with the Massachusetts Institute of Technology Joint Program on the Science and Policy of Global Change. AARON T. WOLF is a professor of geography in the College of Earth, Ocean, and Atmospheric Sciences at Oregon State University.

Read more from the Mozambique News Agency.


MIT and U.N. researchers team up to tackle some of the heftiest climate change challenges developing countries will face as they confront an uncertain future.

Higher temperatures, extreme flooding, longer droughts — for those living in the developed world, the symptoms of climate change mean building higher bridges and paying more for a bowl of cereal. But for those in low-income countries trying to grow and develop, climate change is yet another roadblock.

"In developing countries — and particularly in Africa — they're building their infrastructure at a very fast rate. They're also the most vulnerable to climate change impacts like flooding," says Ken Strzepek, a researcher with MIT's Joint Program on the Science and Policy of Global Change, who has joined forces with the United Nations University-World Institute for Development Economics Research (UNU-WIDER) to help policymakers use a holistic approach to their development strategies.

He and his MIT colleague Adam Schlosser traveled to Finland to present their research at a UNU-WIDER conference last week. The conference was an opportunity to share the results of a multi-study analysis sponsored by UNU-WIDER and released in August as a special edition version of the journal Review of Development Economics. Strzepek was a co-editor.

In their research, Strzepek and colleagues from the Universities of Copenhagen and Colorado take temperature and precipitation projections and look at how flooding, droughts and other impacts of climate change could shape factors such as crop yields, roads and energy infrastructure — all critical for a nation's growth. In doing so, they help governments in these low-income countries decide "Do we adapt now to an uncertain future? Or do we wait and potentially pay more later?" Strzepek says.

Knowing what is unknown

The researchers' main conclusion from their work is that there is so much overall uncertainty surrounding the impacts of climate change that how a country should respond depends largely on very specific factors.

Strzepek gave Tanzania as one example from his research. Like most living in developing nations, the people of Tanzania rely heavily on rain-fed agriculture. Because of the potential for increases in floods and droughts, climate change is seen as a major threat to their main source of food and income. But Strzepek found there was a very large variability in how and how much these changes could affect the country.

"You can't just go to the prime minister and say agriculture is going to go down 20 percent," says Strzepek, "there's too much uncertainty."

But there is very little uncertainty when Strzepek looked at Mozambique. There, it was clear that flooding and sea level rise would be two critical threats to the economy, and in particular to roads needed to transport food from rural farms to city populations.

"So it would make sense for the government to spend the money now to build the roads in a way that makes them less vulnerable in the future," Strzepek says.

As a third example, he studied the development of hydropower in Ethiopia, which they plan to use as an electricity export to help fund roads, schools and other social investments. In studying future impacts to hydropower, Strzepek finds that by 2050 climate change could both positively and negatively affect the energy source. But in the short term, he recommends that the government continue their plan.

"Climate change won't affect the plans that are under way now," Strzepek says. "In 15 years, we'll know a lot more about the direction of climate change and we'll be able to adapt at that time."

Strzepek found too much uncertainty to act in Tanzania, too much not to act in Ethiopia, and very little uncertainty in Mozambique. While the case studies are a needed first step at shedding light on the harsh realities of developing under climate change, much is still unclear.

With the current approach, "you can only look at the extremes," Strzepek says. "Policymakers don't like extremes or worst case scenarios because they can't afford to plan for the worst case scenarios. They like to see what is the likelihood of different outcomes."

That is the next phase of the research. Strzepek and Schlosser are beginning to use the MIT Integrated Global System Modeling (IGSM) framework, which, on a global scale, quantifies the likelihood of various climate predictions and compares them with different policies. They are now bringing this technique down to a regional scale.

Schlosser previewed this approach at the UNU-WIDER conference, while Strzepek gave an example of how it could be used.