Assessing the cascading impacts of natural disasters

By Asjad Naqvi and Irene Monasterolo from the IIASA Advancing Systems Analysis Program

Asjad Naqvi and Irene Monasterolo discuss a framework they developed to assess how natural disasters cascade across socioeconomic systems.

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The 2021 Nobel Prize for Physics, was awarded to the topic of “complex systems”, highlighting the need for a better understanding of non-linear interactions that take place within natural and socioeconomic systems. In our paper titled “Assessing the cascading impacts of natural disasters in a multi-layer behavioral network framework”, recently published in Nature Scientific Reports, we highlight one such application of complex systems.

In this paper, we develop a framework for assessing how natural disasters, for example, earthquakes and floods, cascade across socioeconomic systems. We propose that in order to understand post-shock outcomes, an economic structure can be broken down into multiple network layers. Multi-layer networks are a relatively new methodology, mostly stemming from applications in finance after the 2008 financial crisis, which starts with the premise that nodes, or locations in our case, interact with other nodes through various network layers. For example, in our study, we highlight the role of a supply-side production layer, where the flows are trade networks, and a demand-side household layer, which provides labor, and the flows are migration flows.

Figure 1: A multi-layer network structure

In this two-layer structure, the nodes interact, not only within, but across layers as well, forming a co-evolving demand and supply structure that feeds back across each other. The interactions are derived from economic literature, which also allow us to integrate behavioral responses to distress scenarios. This, for example, includes household coping mechanisms for consumption smoothing, and firms’ response to market signals by reshuffling supply chains. The price signals drive flows, which allows the whole system to stabilize.

We applied the framework to an agriculture-dependent economy, typically found in low-income disaster-prone regions. We simulated various flood-like shock scenarios that reduce food output in one part of the network. We then tracked how this shock spreads to the rest of the network over space and time.

Figure 2: Evolution of vulnerability over time

Our results show that the transition phase is cyclical and depends on the network size, distance from the epi-center of the shock, and node density. Within this cyclical adjustment new vulnerabilities in terms of “food insecurity” can be created. Then, we introduce a new measure, the Vulnerability Rank, or VRank, to synthesize multi-layer risks into a single index.

Our framework can help inform and design policies, aimed at building resilience to disasters by accounting for direct and indirect cascading impacts. This is especially crucial for regions where the fiscal space is limited and timing of response is critical.

Reference:

Naqvi, A. & Monasterolo, I. (2021). Assessing the cascading impacts of natural disasters in a multi-layer behavioral network framework. Scientific Reports 11 e20146. [pure.iiasa.ac.at/17496]

Note: This article gives the views of the author, and not the position of the Nexus blog, nor of the International Institute for Applied Systems Analysis.

Let’s not be arrogant about climate change adaptation

By Marina Andrijevic, researcher in the IIASA Energy, Climate, and Environment Program

Marina Andrijevic tackles some inconvenient but fundamental issues around climate change adaptation.

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Anyone who followed climate-related headlines this summer would have noticed a more than usual amount of talk on climate change adaptation. As it goes with sudden epiphanies in aftermaths of humanitarian disasters in our Western realities, this time we’ve come to realize that we need to seriously think about doing some adaptation.

To be fair, the realization that adaptation is inevitable has for a long time been somewhat of a taboo in the “woke” climate policy and activist circles (the author of this blog is a millennial and would like to acknowledge that the reader’s idea of a long time in climate policy might be different). Admitting that there might be no other option but to adapt to whatever the locked-in effects of climate change are, is arguably defeatist and gives in to the notion that mitigation alone won’t cut it.

While this might be yet another depressing but accurate reflection of the reality under climate change, portraying adaptation and mitigation as different but equally urgent actions could set a dangerous trap if it produces ideas such as: if we adapt enough, perhaps our economies and energy systems won’t need to change so much.

Even if it would be enough (which it wouldn’t), adaptation will not necessarily just happen once we recognize it needs to be done, because the needs and abilities for it operate on different time horizons and geographical scales. Many parts of the world that need adaptation will not necessarily be able to take action, so we have to be very careful when we count on it as a solution to climate change.

This is where we must tackle some inconvenient but fundamental issues about adaptation. Climate change research, especially the areas positioned at the “interface” with policy, could play a crucial role here. In this role, it must be very prudent and avoid doing a disservice to decision makers, and even worse, to people affected by those decisions. In other words, the scientific assessments need to be careful when assuming for whom, where, and how adaptation can reasonably be expected.

We tried to illustrate why this matters in our recent paper that looks at the capacity of populations to adapt to heat stress. We used air-conditioning as a popular, albeit not (yet) climate-friendly adaptation option. My coauthors and I understand that air conditioning could well be maladaptation, meaning that it causes more harm than good in the long-run. Adaptation practices, however, it turns out, are quite difficult to measure, while installed air conditioners can literally be counted, which makes them handy for plugging into our statistical models. We contend with access to air conditioning currently being a good enough example of access to adaptation and promise to assess more options in the future.

Our paper shows how the capacities to protect against heat stress vary widely around the world. Like with many other unjust manifestations of climate change, people in the world’s hottest areas also have the least means to adapt. We found that countries with more income, more urban areas, and less income inequality, are also the ones where more people have access to air conditioning.

This does not come as the world’s biggest revelation, but it conveniently allows us to make informed guesses on how access to air conditioning might change in 2050 or 2100. This is possible because the research community has already engaged in a group effort to propose five different futures with regard to GDP, urbanization, and income distribution (in climate jargon: the Shared Socioeconomic Pathways or SSPs).

Coupling the potential rates of air conditioning with the people exposed to heat stress based on projections of climate models, lets us calculate the cooling gap – the difference between people exposed to heat stress and people who can protect themselves against it with the use of air conditioning.

Depending on whether we find ourselves in the best- or the worst-case scenario of socioeconomic development could mean anywhere between two billion and five billion people globally unable to protect themselves against heat stress with air conditioning in 2050. This range only grows with longer time horizons, with Sub-Saharan Africa and South Asia being the areas of the world where these differences are the starkest.

We hope that our paper will motivate further investigations of potential gaps in adaptation that point to insufficient adaptive capacity and help to identify the areas and populations most at risk, as well as what additional work needs to be done in terms of socioeconomic improvements before we can reasonably expect adaptation to take place. Our findings on the importance of factors beyond just GDP, suggest that helping communities to build their adaptive capacity doesn’t mean only throwing money at them (although that would make for a decent start!), but international efforts must focus on issues such as eradicating inequalities, supporting smart urban development, strengthening institutions, and providing education.

So, let’s not take it for granted that we will all be able to adapt either now or in the future. Eliminating the causes of climate change must remain the number one policy objective that will help to reduce the need for adaptation in the first place. But number two could be helping communities that have no option but to cope with what’s already coming at them. Highlighting in our research what the implications of different adaptive capacities are for preservation of livelihoods, is a small step towards achieving this.

Reference:

Andrijevic, M., Byers, E., Mastrucci, A., Smits, J., & Fuss, S. (2021). Future cooling gap in shared socioeconomic pathways. Environmental Research Letters 16 (9) e094053. [pure.iiasa.ac.at/17411]

Note: This article gives the views of the author, and not the position of the Nexus blog, nor of the International Institute for Applied Systems Analysis.

Warming waters, evolution, and the future for fisheries policy

By Neema Tavakolian, 2021 IIASA Science Communication Fellow 

Young Scientists Summer Program (YSSP) participant Lyndsie Wszola explores how human interactions with warming freshwater systems have affected the evolution of fish species through the lens of the North American walleye. 

© Justinhoffmanoutdoors | Dreamstime.com

The effects of climate change have intensified over the past few years, especially in our oceans, and human based activities contributing to it are now being taken more seriously. While the warming of our oceans is indeed troubling, many forget that freshwater systems are also being influenced, and that this is affecting the growth and evolution of the species that reside in them.

2021 YSSP participant Lyndsie Wszola wants to explore changes in freshwater systems using human-natural modeling systems at IIASA.

© Lyndsie Wszola

Growing up with a conservation officer father, Wszola is a second-generation conservationist. Knowing she wanted to enter this field at an early age, she realized that she had to get into research and academia first. Her main interests while studying at the University of Nebraska have been the interactions between humans and wildlife.

While researching the relationships between hunters and ring-necked pheasants, she discovered an affinity for quantitative research. This curiosity went even further after she discovered literature on harvest induced evolution and mathematical ecology specifically pertaining to fish populations. Together, this initial desire to explore human and wildlife interactions and her newfound interest in mathematical ecology, led Wszola to take a closer look at North American freshwater systems and how we as humans are influencing its ecology. Her research specifically delves into the growth and evolutionary changes seen in the North American walleye (Sander vitreus) – a popular fish in Canada and the United States. The reason for its fame is its palatable taste as a freshwater fish and its status among anglers, making it both a commercially and recreationally fished species.

Walleye was chosen as the subject of Wszola’s research for many reasons. First, walleye, like many fish, are ectotherms meaning that their body processes and behaviors are directly linked to their body temperature, which is in turn directly linked to the temperature of the water. Unlike other fish however, there is already plenty of research and data on the relationship between the walleye’s growth and temperature. This information makes it much easier to simulate the walleye’s eco-evolutionary growth dynamics in the context of human driven harvests in warming waters. Wszola will also be working with very large datasets spanning multiple latitudes ranging from Ontario, Canada down to Nebraska, USA. The datasets include up to six million fish with four million of those being walleye.

“My goal is to model the influence of temperature on fish harvests based on size. Due to their ectotherm nature, we can observe the changes in body size in annual harvests. As waters warm, walleye grow much faster. We also know that intensely harvested fish often evolve to reach maturation at smaller sizes. When coupled with rising temperatures, this relationship between harvest induced and temperature induced evolution can be fascinating, as we now have two sources working together to change the growth evolution of this fish,” she explains.

Due to warming temperatures, many natural resources are at stake with some of the most sensitive being aquatic in nature. Research like this is important as it allows us to look at our relationships with the environment to be able to react accordingly.

“I hope that the research I do yields fascinating enough results so that from a practical standpoint, future fisheries policies can include climate change dynamics in addition to fish and human dynamics,” Wszola concludes.

Note: This article gives the views of the author, and not the position of the Nexus blog, nor of the International Institute for Applied Systems Analysis.

Making the Top 100 in Ecology: the story of a successful research paper

By Florian Hofhansl, researcher in the Biodiversity, Ecology, and Conservation Research Group of the IIASA Biodiversity and Natural Resources Program

Florian Hofhansl writes about a successful paper on which he was the lead author that was recently ranked #32 on the list of the Top 100 most downloaded ecology papers published in 2020.

Early in 2020, one of my manuscripts titled “Climatic and edaphic controls over tropical forest diversity and vegetation carbon storage” was accepted for publication in the prestigious journal Nature Scientific Reports.

Initially, I was worried about the bad timing when I was informed that the paper would be published on 19 March – right at the onset of the COVID-19 pandemic – since it took me and my colleagues almost a decade to collect the data and publish our results on the biodiversity and functioning of tropical forest ecosystems.

However, my worries completely disappeared when I learned that our research article had received more that 3,000 downloads, placing it among the top 100 downloaded ecology papers for Scientific Reports in 2020. This is an extraordinary achievement considering that Scientific Reports published more than 500 ecology papers in 2020. Seeing our paper positioned at #32 of the top 100 most downloaded articles in the field, therefore meant that our science was of real value to the research community.

We kicked off our study in the dry-season of 2011 by selecting twenty one-hectare forest inventory plots at the beautiful Osa peninsula – one of the last remnants of continuous primary forest – located in southwestern Costa Rica. We did not expect that our project would receive this much scientific recognition as we were merely interested in describing the stunning biodiversity of this remote tropical region. Nevertheless, we were striving to understand the functioning of the area’s megadiverse ecosystem by conducting repeated measurements of forest characteristics, such as forest growth, tree mortality, and plant species composition.

After periodically revisiting the permanent inventory plots, and recording data for almost a decade, we found stark differences in the composition of tropical plant species such as trees, palms, and lianas across the landscape. Most interestingly, these different functional groups follow different strategies in their competition for light and nutrients, both limiting plant growth in the understory of a tropical rainforest. For instance, lianas – which are long-stemmed, woody vines – are relatively fast growing and try to reach the canopy to get to the sunlight, but they do not store as much carbon as a tree stem to reach the same height in the canopy. In contrast, palms share a different strategy and mostly stay in the lower sections of the forest where they collect water and nutrients with their bundles of palm leaves arranged upward to catch droplets and nutrients falling from above, thus reducing local resource limitation.

Lead author Florian Hofhansl and field botanist, Eduardo Chacon-Madrigal got stuck between roots of the walking palm (Socratea exorrhiza), while surveying one of the twenty one-hectare permanent inventory plots © Florian Hofhansl

Our results indicate that each plant functional group – that is, a collection of organisms (i.e., trees, palms, or lianas) that share the same characteristics – was associated with specific climate conditions and distinct soil properties across the landscape. Hence, this finding indicates that we would have to account for the small-scale heterogeneity of the landscape in order to understand future ecosystem responses to projected climate change, and thus to accurately predict associated tropical ecosystem services under future scenarios.

Our study and its subsequent uptake by the research community, illustrates the value of conducting on-site experiments that empower researchers to understand crucial ecosystem processes and applying these results in next-generation models. Research like this makes it possible for scientists to evaluate vegetation–atmosphere feedbacks and thus determine how much of man-made emissions will remain in the atmosphere and therefore might further heat up the climate system in the future.

Our multidisciplinary research project furthermore highlighted that it is crucial to gather knowledge from multiple disciplines, such as botany (identifying species), plant ecology (identifying functional strategies), and geology (identifying differences in parent material and soil types) – since all of these factors need to be considered in concert to capture the complexity of any given system, when aiming to understand the systematic response to climate change.

Read more about the research here: https://tropicalbio.me/blog

Reference:

Hofhansl F, Chacón-Madrigal E, Fuchslueger L, Jenking D, Morera A, Plutzar C, Silla F, Andersen K, et al. (2020). Climatic and edaphic controls over tropical forest diversity and vegetation carbon storage. Scientific Reports DOI: 10.1038/s41598-020-61868-5 [pure.iiasa.ac.at/16360]

Note: This article gives the views of the author, and not the position of the Nexus blog, nor of the International Institute for Applied Systems Analysis.

Multiple benefits of Disaster Risk Reduction investments

By Julian Joseph, research assistant in the Water Security Research Group

Julian Joseph explains the concept of the triple dividend of disaster risk reduction investments based on the application of a novel economic model applied to a case study undertaken in Tanzania and Zambia.

What are the benefits of Disaster Risk Reduction (DRR) investments such as dams and the introduction of drought-resistant crops in agriculture for an economy? They are threefold and called the “triple dividend” of DRR investments. The first dividend comprises the direct effects of DRR investments, which limit damage to houses, infrastructure, and other physical assets and prevent death and injury. The second dividend unlocks the economic potential of an economy because risk reduction drives people and businesses to invest more, as they expect less of what they invest in to be destroyed by disasters, while the third dividend is comprised of development co-benefits through other uses the investments provide.

© Gerrit Rautenbach | Dreamstime.com

Using a new macroeconomic model called DYNAMMICs, my colleagues and I have found that there is often a significant growth effect for the economy attached to investing in mitigation measures like dams and drought resistant crops, which is commonly underestimated in traditional models. One reason for this is the focus of other models on only the first, direct dividend. We specifically looked into the examples of Tanzania and Zambia, which show that governments and other stakeholders in developing countries can spur economic growth by investing in DRR measures, thus increasing future earnings and creating a safe environment for investments into other economic activities.

In Tanzania and Zambia, floods affect tens of thousands of people each year (on average 45,000 or .08% of the population in Tanzania and 20,000 or .11% of the population in Zambia). Droughts have more widespread consequences and already affect 11.8% of the population in Tanzania and 19% of Zambians who often lose all or parts of their harvest. This poses an imminent threat to food security in countries where substantial shares of the population rely on subsistence farming as their primary source of income. Given the effects of climate change, these numbers and their ramifications are bound to become ever more pressing issues. However, policymakers, institutions, enterprises, and individuals tend to underinvest in adaption measures.

A promising avenue for demonstrating the potential of DRR investments is offered by including all economic growth effects they invoke into policy analysis, thus showing that besides risk reduction and post-disaster mitigation of destruction, investing in DRR measures can help countries achieve many of their other development goals as well.

We tend to only think of the first dividend of DRR investments, the direct effects of which stop people from being immediately affected by disasters. In the case of Tanzania and Zambia, we examined, among others, the benefits of constructing additional dams. The direct benefits of dams lie in the safeguarding of livelihoods, infrastructure, housing, and agricultural production. These are seen as the first dividend, called the ex-post damage mitigation effect. There are however also additional co-benefits.

In both Tanzania and Zambia, large shares of the population are heavily dependent on agriculture, which makes the introduction of drought-resistant crop varieties such an additional benefit. These crop varieties do not only help farmers preserve their yields in times of disastrous droughts, but additionally support farmers by generating higher yields, even in the absence of disaster. This effect is boosted by the lowered risk for the loss of crops, which spurs investment into farming activities and inputs. Farmers who do not fear losing their entire harvest can, and generally will, invest more into the production of this crop – an example of the second type of dividend, the ex-ante risk reduction effect. This type of economically beneficial effect materializes regardless of the onset of disaster.

The same is true for the third type of dividend, the co-benefit production expansion effect, which is especially relevant for the advantages of dams. The power generation capability of dams, leads to much larger economic gains than the two other dividends combined. In countries such as those at hand with frequent power cuts and comparably low levels of electrification, especially in rural areas, the additional electricity generated can lead to particularly pronounced positive effects by supplying economic actors with access to power. In other scenarios, the provision of ecosystem services is also an important effect falling into this category.

The results we obtained using the DYNAMMICs model are promising: Constructing only two additional dams leads to a 0.3% increase of GDP growth in Tanzania for the next 30 years (0.2% in Zambia) with results largely (97%) driven by the co-benefit production expansion effect. Similarly, the introduction of drought resistant crops and exposure management (i.e., land use restrictions) significantly boost economic growth perspectives. Finally, introducing insurance is a driver for a reduction in the variance of GDP growth, which helps to reduce uncertainty for everyone in the economy. Modeling in such a fashion is therefore an important means of weighing policy options for DRR against each other and for determining optimal levels of investment.

Note: This article gives the views of the author, and not the position of the Nexus blog, nor of the International Institute for Applied Systems Analysis.

Addressing the youth’s climate justice concerns

By Thomas Schinko, Acting Research Group Leader, Equity and Justice Research Group

Thomas Schinko introduces an innovative and transdisciplinary peer-to-peer training program.

What do we want – climate justice! When do we want it – now! The recent emergence of youth-led, social climate movements like #FridaysForFuture (#FFF), the Sunrise Movement, and Extinction Rebellion has reemphasized that at the heart of many – if not all – grand global challenges of our time, lie aspects of social and environmental justice. With a novel peer-to-peer education format, embedded in a transdisciplinary research project, the Austrian climate change research community responds to the call that unites these otherwise diverse movements: “Listen to the Science!”

The climate crisis raises several issues of justice, which include (but are not limited to) the following dimensions: First, intragenerational climate justice addresses the fair distribution of costs and benefits associated with climate change mitigation and adaptation, as well as the rectification of damage caused by residual climate change impacts between present generations. Second, intergenerational justice focuses on the distribution of benefits and costs from climate change between present and future generations. Third, procedural justice asks for fair processes, namely that institutions allow all interested and affected actors to advance their claims while co-creating a low-carbon future. Movements like #FFF maneuver at the intersection of those three forms of climate justice when calling on policy- and decision makers to urgently take climate action, since “there is no planet B”.

Along with the emergence of these youth-led social climate movements came an increasing demand for the expertise of scientists working in the fields of climate change and sustainability research. To support #FFF’s claims with the best available scientific evidence, a group of German, Austrian, and Swiss scientists came together in early 2019 as Scientists for Future. Since then, requests from students, teachers, and policy and decision makers for researchers to engage with the younger generation have soared, also in Austria. Individual researchers like me have not been able to respond to all these requests at the extent we would have liked to.

In this situation of high demand for scientific support, the Climate Change Center Austria (CCCA) and The Federal Ministry of Education, Science and Research (BMBWF) have put their heads together and established a transdisciplinary research project – makingAchange. By engaging early on with our potential end users – Austrian school students – a truly transdisciplinary team of researchers as well as practitioners in youth participation and education (the association “Welt der Kinder”) has co-developed this novel peer-to-peer curriculum. The training program, which runs over a full school year, sets out to provide the students not only with solid scientific facts but also with soft skills that are needed for passing on this knowledge and for building up their own climate initiatives in their schools and municipalities. One of the key aims is to provide solid scientific support while not overburdening the younger generation who often tend to put too high demands on themselves.

Establishing scientific facts about climate change and offering scientific projections of future change on its own does not drive political and societal change. Truly inter- and transdisciplinary research is needed to support the complex transformation towards a sustainable society and the integration of novel, bottom-up civil society initiatives with top-down policy- and decision making. Engaging multiple actors with their alternative problem frames and aspirations for sustainable futures is now recognized as essential for effective governance processes, and ultimately for robust policy implementation.

Also, in the context of makingAchange it is not sufficient to communicate science to students in order to generate real-world impact in terms of leading our societies onto low-carbon development pathways. What is additionally needed, is to provide them with complementary personal and social skills for enhancing their perceived self-efficacy and response efficacy, which is crucial for eventually translating their knowledge into real climate action in their respective spheres of influence.

Recent insights from a medical health assessment of the COVID-19 related lockdowns on childhood mental health in the UK have shown that we are engaging in an already highly fragile environment. In addition, a recent representative study for Austria has shown that the pandemic is becoming a psychological burden. The study authors are particularly concerned about young people; more than half of young Austrians are already showing symptoms of depression. Hence, we must engage very carefully with the makingAchange students when discussing the drivers and potential impacts of the climate crises. Particularly since some of them are quite well informed about research, which has shown (by using a statistical approach) that our chances of achieving the 1.5 to 2°C target stipulated in the Paris Agreement are now probably lower than 5%. Another example of such alarming research insights comes in the form of a 2020 report by the World Meteorological Organization, which warns that there is a 24% chance that global average temperatures could already surpass the 1.5°C mark in the next five years.

Zoom group picture taken at the end of the second online makingAchange workshop for Austrian school students. Copyright: makingAchange

The first makingAchange activities and workshops have now taken place – due to the COVID-19 regulations in an online format, which added further complexity to this transdisciplinary research project. Nevertheless, we were able to discuss some of the hot topics that the young people were curious about, such as the natural science foundations of the climate crisis, climate justice, or a healthy and sustainable diet. At the same time, we provided our students with skills to further transmit this knowledge and to take climate action in their everyday live – such as a climate friendly Christmas celebration in 2020. The school student’s lively engagement in these sessions as well as the overall positive (anonymous) feedback has proven that we are on the right track.

The role of science is changing fast from “advisor” to “partner” in civil society, policymaking, and decision making. By doing so, scientists can play an important, active role in implementing the desperately needed social-ecological transformation of our society without becoming policy prescriptive. With the makingAchange project, we are actively engaging in this transformational process – currently only in Austria but with high ambitions to scale-out this novel peer-to-peer format to other geographical and cultural contexts.

Note: This article gives the views of the author, and not the position of the Nexus blog, nor of the International Institute for Applied Systems Analysis.