Compound Weather Extremes/Cascading Events
Background and Purpose
Compound events encompass a broad spectrum of possibilities, triggered when two or more hazard events or climate variables when juxtaposed in space and time amplify the overall impact and severity implied by the underlying events. The Intergovernmental Panel on Climate Change defines compound events as (a) two or more extreme events occurring simultaneously or successively, (b) combinations of extreme events with underlying conditions that amplify the impact of the events, or (c) combinations of events that are not themselves extremes but lead to an extreme event or impact when combined[1]. Climate change is tipping the balance for more extreme weather to occur more frequently. This is increasing the risk of the heretofore little-explored phenomenon of weather/climate related compound events – the net impact of which is considerably greater than the sum of the individual damages attributable to the underlying events.
Zscheischler et al. (2020) further classified compound weather events into four different basic types: (1) preconditioned, where a weather-driven or climate-driven precondition aggravates the impacts of a hazard; (2) multivariate, where multiple drivers and/or hazards lead to an impact; (3) temporally compounding, where a succession of hazards leads to an impact; and (4) spatially compounding, where hazards in multiple connected locations cause an aggregated impact.
One example of type (1) is where a region receives a crippling amount of snow in a short period of time followed closely by a dramatic warm spell with heavy rain. The heavy snow, in addition to possibly collapsing roofs, has resulted in clogged storm drains and sewer openings. The subsequent heavy rain causes flooding of streets and damage to interior property and contents which would not necessarily have occurred to the extent it did were it not for the great intensity of the snowfall or the intensity of the warm wet spell or the proximity between the two. Climate change by virtue of intensifying atmospheric circulations and allowing more moisture to exist in the atmosphere is contributing to such possibilities.
With these issues in mind, the Society of Actuaries (SOA) Research Institute’s Catastrophe and Climate Strategic Research Program (“sponsors”) is soliciting research proposals that will further explore this topic. The purpose of this Request for Proposals (RFP) is to motivate research to better understand how much more frequent and/or intense compound events can be in the future because of climate change, and what would be their impact on the physical environment, agriculture, human health and mortality and to our ecosystem.
Climate change impacts to compound events may be evaluated from a variety of different perspectives, although preference will be given to proposals that focus more on impacts to property and life.
Research Objective
The sponsors are seeking researchers to explore the multifaceted impacts of climate change on compound weather events. The desired deliverable is a report that describes one or more aspects of how compound event risk could be influenced by climate change and the likely impact to property and life. This could be supported through analysis of future climate output from General Circulation or other climate models and statistical and dynamic modeling approaches by extrapolation of how an actual event in the past could manifest in the future (e.g., case study). This can further be supported by a brief review of existing literature, a case study with datasets, regional mapping, and other statistical and socio-physical approaches as needed.
The following are just a few examples to get you started:
Flood following Fire (type 1)
Large-scale wildfires dramatically alter the terrain and ground conditions. Normally, vegetation absorbs rainfall, reducing runoff. However, wildfires leave the ground charred, barren, and unable to absorb water, creating conditions ripe for flash flooding and mudflow. Wildfires are becoming more prevalent in the western U.S. in part because of climate change which is increasing the regional aridity as average temperatures increase. Heavy precipitation events are also becoming more frequent in the region. How much more frequently these separate and very different weather (related) extremes will occur is an important consideration for improving resiliency. Specific sample topics of research could include:
- Evaluating how fire weather days and heavy precipitation days will change in the future in terms of frequency, seasonality, geography
- Evaluating the impact to communities or regions in terms of how much more property damage or destruction could occur from changes in the frequency, intensity, or location of such events
Heat stress exacerbated by declining wind speeds (type 2)
Heat waves are increasing in frequency and severity. Stalled winds can amplify the impact by reducing the evaporative cooling effect, posing a significant risk to livestock. Strained power grids providing intermittent relief can elevate mortality and morbidity risk of the most vulnerable population. Specific sample topics of research could include:
- Analyzing how average wind speeds are expected to evolve in the U.S.? (Per the latest IPCC report, wind speeds are expected to drop in Europe due to climate change)
- Identifying what geographical regions may become most vulnerable because of combined increase in frequency and intensity of such events and hitherto cooler climates that did not warrant central air-conditioning
- Estimating increased mortality to life (e.g., livestock and people) in that region
Long Lived Flow Patterns (type 3)
The same type of extreme weather event, even if not extreme by itself, can, if repeated over the same region multiple times, cause an amplification of damage. Large scale weather patterns may stall more frequently over a location because of climate change causing the same type of weather to occur over the same region multiple times. This blocking pattern allows precipitating weather systems to follow one another over the same location in train-like fashion. The “training effect” can ultimately cause flooding repeatedly and for a prolonged amount of time. Specific sample topics of research could include:
- Explaining how the persistence or longevity of large-scale weather patterns (blocking), like a large-scale pressure trough in the eastern U.S., change in the future
- Estimating the increased flood risk (e.g., to people and property)
Global Simultaneous Extremes (type 4)
The El Nino Southern Oscillation phenomenon is known to have worldwide impacts, that can cause water and food shortages, power outages, and heat stress, among others. In the future, more extreme weather events will mean increased likelihood for more simultaneous extreme events that will cause impacts to global health, the global supply chain, and global reinsurance. Specific sample topics of research could include:
- Estimating how much more frequently multiple simultaneous global weather-related extremes may occur in the future
- Evaluating the impact to human health, business interruption, reinsurance losses
Note that the list above is not meant to be exhaustive but merely examples of proposed topics that may be researched. Nor is it required that the resulting resource address all of the above listed issues. Proposers should thoroughly describe issues on which they intend to focus in their proposals.
Proposal Requirements
To facilitate the evaluation of proposals, the following information should be submitted:
- Resumes of the researcher(s), including any graduate student(s) expected to participate, indicating how their background, education and experience bear on their qualifications to undertake the research. If more than one researcher is involved, a single individual should be designated as the lead researcher and primary contact. The person submitting the proposal must be authorized to speak on behalf of all the researchers as well as for the firm or institution on whose behalf the proposal is submitted.
- An outline of the approach to be used (e.g., literature search, model, etc.), emphasizing issues that require special consideration. Details should be given regarding the techniques to be used, collateral material to be consulted, and possible limitations of the analysis.
- A description of the expected deliverables and any supporting data, tools or other resources.
- Cost estimates for the research, including computer time, salaries, report preparation, material costs, etc. Such estimates can be in the form of hourly rates, but in such cases, time estimates should also be included. Any guarantees as to total cost should be given and will be considered in the evaluation of the proposal. While cost will be a factor in the evaluation of the proposal, it will not necessarily be the decisive factor.
As a guide for developing the project budget, please review the Historical Project Cost Guide (see Appendix) - A schedule for completion of the research, identifying key dates or time frames for research completion and report submissions. The General Insurance Research Committee is interested in completing this project in a timely manner. Suggestions in the proposal for ensuring timely delivery, such as fee adjustments, are encouraged.
- Other related factors that give evidence of a proposer's capabilities to perform in a superior fashion should be detailed.
Selection Process
The Catastrophe & Climate Strategic Research Program will appoint a Project Oversight Group (POG) to oversee the project. The Steering Committee is responsible for recommending the proposal to be funded. Input from other knowledgeable individuals also may be sought, but the Program Steering Committee will make the final recommendation, subject to Society of Actuaries Research Institute (SOA) leadership approval. An SOA staff research actuary will provide staff actuarial support.
Questions
Any questions regarding this RFP should be directed to Rob Montgomery, SOA Research Project Manager at rmontgomery@soa.org or +1-740-258-2977.
Notification of Intent to submit Proposal
If you intend to submit a proposal, please email written notification to Erika Schulty at eschulty@soa.org
Submission of Proposal
Please email your proposal to Erika Schulty at eschulty@soa.org; proposals must be received no later than May 10, 2023. It is anticipated that all proposers will be informed of the status of their proposal by Mid-June 2023.
Conditions
The selection of a proposal is conditioned upon and not considered final until a Letter of Agreement is executed by both the Society of Actuaries Research Institute and the researcher.
The Society of Actuaries Research Institute reserves the right to not award a contract for this research. Reasons for not awarding a contract could include, but are not limited to, a lack of acceptable proposals or a finding that insufficient funds are available. The Society of Actuaries Research Institute also reserves the right to redirect the project as is deemed advisable.
The Society of Actuaries Research Institute plans to hold the copyright to the research and to publish the results with appropriate credit given to the researcher(s).
The Society of Actuaries Research Institute may choose to seek public exposure or media attention for the research. By submitting a proposal, you agree to cooperate with the [Society of Actuaries/sponsoring entity] in publicizing or promoting the research and responding to media requests.
The Society of Actuaries may also choose to market and promote the research to members, candidates and other interested parties. You agree to perform promotional communication requested by the Society of Actuaries Research Institute, which may include, but is not limited to, leading a webcast on the research, presenting the research at an SOA meeting, and/or writing an article on the research for an SOA newsletter.
Conflict of Interest
You agree to disclose any of your material business, financial and organizational interests and affiliations which are or may be construed to be reasonably related to the interest, activities and programs of the Society of Actuaries Research Institute.
Appendix
The cost ranges below are intended as a guide for budgeting project costs for proposals in response to SOA Research Institute Request for Proposals (RFP). Please note these figures span the 33rd to 66th percentiles for all projects as well as projects that involve a specific approach (lit review, survey, etc.). They are based on historical costs over several recent years. Expected costs for some RFPs may fall outside these ranges depending on the nature of the work and resources required for completion.
All Contracted Projects
This category includes all contracted projects that the Institute has undertaken within the last several years.
The 33rd-66th percentile project costs range is $25,000 - $50,000.
Literature Reviews
This category includes projects that involved only a literature review or the cost for the portion of a larger project that included a literature review.
The 33rd-66th percentile project costs range is $15,000 - $20,000.
Surveys
This category includes all projects that had a survey as their primary component.
The 33rd-66th percentile project costs range is $28,000 - $55,000.