WIXLIB

6.00100yr Precipitation Event (in) andExtreme Events during 2010-20209.655.436.255.134.486.257.316.00 7.186.155.976.52Future Projections5.186.005.755.505.257.5010.52Inches500 year, or 1000 year events like thoseexperienced in Northern Wisconsin during2012, 2016, and 2018; or in August 2018 inSouth Central Wisconsin – are most stronglyaffected by a warming climate. While theseevents are rare, they are also exceedinglydamaging and are becoming disproportionatelymore common globally as our climate warms.5.00To produce projections of temperature and4.755.75precipitation into the 21st century, the 20117.567.1011.634.50WICCI Assessment Report used the University6.334.256.12of Wisconsin Probabilistic Downscaling DataVersion 1. This data uses a “statisticalNOTES: The extreme rainfall events are the largest independent events that exceeded the 100yr threshold.If an extreme event was recorded at numerous locations, only the largest recorded value was showed.downscaling” technique in which global scaleAny two-day events were classified by their largest value recorded.Figure 4. Climatological100yr rainfall event magnitudeSOURCE: Nelson Institute, Center for Climatic Research, UW-MadisonDATA: UWPD Downscaled Dataclimate model projections are combined with(shading) together with historical extreme rainfall events overlocal observations to produce estimates ofthe time period 2010-2020 (dots with numbering). Each eventclimate variations and change over a moreis the largest daily rainfall recorded at a given location over thelocalized scale. This update uses the Universitytime period 2010-2020. For multi-day events, only the day withof Wisconsin Probabilistic Downscaling Datathe largest rainfall is recorded. Data from WICCI and E.Version 3 (WICCI Data), which is based onHopkins, State Climatology Office.updated global models and an improvedmethodology. The WICCI Data includes nearly twice as many global models and, like the 2011 Assessment Report,results are presented either as an average over all models (maps), or as a range (10th-90th percentile) of possiblechanges that account for simulated natural variability as well as differences in physical processes across global modelsimulations (e.g. annual warming of 2.5 -7.5 F). The WICCI Climate Working Group has also produced “dynamicallydownscaled” projections in which the global models are used to force high-resolution regional climate models. Thesesimulations provide additional information about potential climatic changes in Wisconsin, and results are reportedfrom the dynamically downscaled projections where relevant.In addition to a change in data source, the methodology for calculating future projections has changed since the 2011WICCI Assessment Report. One major change is that future projections are now calculated relative to a baselineclimatology of 1981-2010 rather than 1960-1999, in order to be consistent with new standards for defining a “climatenormal.”6 Two different emissions scenarios are included where relevant: the RCP4.5 scenario is a “low-end” globalemissions scenario over the next century and the RCP8.5 scenario is a “high-end” or “business as usual” normals7

Figure 5. Projected changes in mid-21st-century (2041-2060) (left) annual, (middle) winter, and (right) summeraverage temperature for RCP4.5 “low-end” emissions scenario. WICCI Data.The WICCI projections show very similar climatic changes to those in the 2011 WICCI Assessment Report. In particular,the WICCI projections show that under the low-end emissions scenario Wisconsin is expected to warm by 2.5 -7.5 Fby mid-century, with maximum warming during winter (3 -8 F) and minimum warming during summer (1.5 -7.5 )(Figure 5). Dynamically downscaled results are similar but have larger warming rates for summer due to increased drysoil conditions. For mid-century, projections for the high-end emissions scenario are very similar to the low-endscenario, with annual mean warming of about 3 F-9 F by mid-century. By late century (2081-2100) projections ofannual mean temperature for the low-end and high-end emissions scenarios differ substantially with the low-endemissions scenario projecting annual mean changes of 3 -10 F, and the high-end emissions scenario projectingchange of 7 -16 F (Figure 6). These drastic warming rates for the high-end emissions scenario indicate the importanceof mitigation for reducing impactsof climate change.Changes in mean temperature arealso manifest on a daily basis bychanges in the characteristics ofextreme heat events. By midcentury, the number of extremelyhot days in Wisconsin is likely totriple (defined as the number ofdays where temperature exceeds90 F; Figure 7), and the number ofextremely hot nights is likely toquadruple (defined as the numberof nights when daily temperaturedoes not drop below 70 F). It isFigure 6. Projected changes in late-21st-century (2081-2100) annual averagetemperature for the (left) RCP4.5 “low-end” and (right) RCP8.5 “high-end”emissions scenario. WICCI Data.8

noteworthy that by the late centuryunder the high-emissions scenario,southern Wisconsin may experience80 to 90 days per year – nearly anentire summer – with hightemperatures exceeding 90 F. Theseextreme changes havedisproportionate impacts oncommunities of color, elderly,individuals with existing healthconditions, and economicallydisadvantaged communities wholack cooling capabilities.Figure 7. Annual extreme heat frequency (left) historical and (right)projected mid-21st-century (2041-2060) for the RCP4.5 low-end emissionsscenario. Depicted are the number of days per year when the temperatureexceeds 90 F. WICCI Data.Precipitation is more variable thantemperature, and as a result, futureprojections (Figure 8) have a largerrange of possible changes thantemperature. Annual mean rainfall in Wisconsin is expected to increase by mid-century, but the change variesamong models from a 5% decrease to a 15% increase. During winter, spring, and fall, precipitation is likely to increase,whereas summer precipitation has equal chances of increasing or decreasing. It is likely that extreme precipitationwill increase in Wisconsin, with the very extreme values seeing the largest change. For example, a daily 4”precipitation event typically occurs 6-10 times per 100 year (once every 10-15 year) in Southern Wisconsin. Theseevents are likely to increase in frequency to 10-15 events per 100 year (once every 6-10 years; Figure 9). Thesechanges are even more pronounced for the late-century, high-emissions scenario, which projects 18-22 daily 4”Figure 8. Projected changes in mid-21st-century (2041-2060) (left) annual, (middle) winter, and (right) summeraverage precipitation (percent) for RCP4.5 “low-end” emissions scenario. WICCI Data.9

Figure 9. Projected changes in mid-21st-century (2041-2060) (left) annual,(middle) winter, and (right) summer average precipitation (percent) forRCP4.5 “low-end” emissions scenario. WICCI Data.precipitation events every 100 years (approximately once every 5 years). These extreme precipitation events haveimmense impacts across the state, especially to agricultural communities.Concluding statementNew analyses of observed historical climate trends, as well as new climate projections for Wisconsin provideadditional confidence in expected climate change over the coming century. Observed historical trends showconsistency with greenhouse-gas forced model simulations into the 21st century, especially with respect to observedseasonal changes. Future projections under a low-end emissions scenario suggest Wisconsin will continue to warminto the middle of the 21st century, including a tripling in frequency of extreme heat days. Wisconsin is also likely tobecome wetter in the coming century, with robust increases in winter, spring, and fall. Extreme precipitation eventsare likely to increase in frequency and magnitude. These changes are much larger under a high-end emissionsscenario, pointing to the importance of reducing greenhouse gas emissions in order to limit climate change impacts toWisconsin.10

Subcommittee on Energy, Housing & InfrastructureInvestments in infrastructure are long term. Our rural roads, highways, airports, ports, dams, stormwater andwastewater systems – everything that supports our lives and livelihoods – have been and are currently beingdesigned under climate conditions different than they will encounter during most of their service life. In rebuilding,and in designing new infrastructure, updated climate projections need to drive decisions of how and where to rebuild.Currently, these infrastructure investment decisions often do not take into account expected future changes inextreme weather including precipitation and temperature. This is because specific data on current and future climatevariables are not available or are difficult to access. Although several large infrastructure projects in Wisconsin haveconsidered future climate conditions, most have not, because this is something that is often beyond the limitedresources of infrastructure managers or other decision makers in small communities. Further, many codes andstandards require the usage of climate data that are out of date, and they do not require consideration of anticipatedfuture climate conditions in facility planning. We suggest the following investments and actions to help allcommunities in Wisconsin to have the resources to proactively and efficiently evaluate alternatives and plan repairsand new facilities to consider future climate conditions.Subcommittee on Energy, Housing & InfrastructureStrategies and Solutions TableIssueStrategies and SolutionsClimate DataCreate a State Climate Office and fund staff to more efficiently collect state-wide climate datapublish quantitative data on key climate variables for current and projected future conditions andprovide guidance on ways to promote resiliency to climate change impacts in our communities.InfrastructureEncourage (and require where appropriate) that all new infrastructure planning and designprojects specifically consider vulnerability and risk associated with future climate conditions.Provide new state funding for infrastructure replacement or repair projects to proactively makeinfrastructure more resilient to future changes.Provide a standardized method to evaluate and report embodied carbon emissions from the mostcommonly used construction materials in Wisconsin and create Environmental Product Declarationsfor project development, bid evaluation, etc.Long-term Goals (4-10 years): Pursue climate bonds to accelerate green actionsMississippiRiverDevelop a two-dimensional hydraulic model that will aid in flood forecasting, management,response, and policy on a watershed basis. Use this model to evaluate current and future conditionsfor a variety of scenarios to define transportation, ecological, and planning impacts.11

Subcommittee on Energy, Housing & InfrastructureStrategies and Solutions Table (Continued)IssueStrategies and SolutionsCoastalResilienceConduct vulnerability assessments in coastal communities to identify buildings and criticalinfrastructure such as ports, harbors, and marinas that are highly vulnerable.Promote relocation, elevation, or acquisition/demolition of infrastructure and homes to removethem from hazard areas. Examples: increasing working dock heights, converting marinas to floatingdockage, and relocating water intakes to deeper water.Promote the beneficial use of material dredged from Great Lakes harbors by increasing fundingthat supports harbor dredging that sustainably uses the dredged material or creating new funding.Long-term (4-10 years) prioritiesPromote improved coastal-specific stormwater and groundwater management practices nearcoastal bluff areas through stormwater management plans and ordinances. Coastal-specificstormwater management plans could fund or incentivize practices like directing storm water andseptic discharge away from the bluff, maintaining deep rooted native vegetation, and improvinggroundwater drainage to increase the stability of bluffs.12

Making climate information available and usable for Wisconsin CommunitiesRecent extreme weather events throughout Wisconsin have shown theshortcomings of existing infrastructure and disaster relief systems. Theyhave also highlighted the need for providing communities with the bestavailable weather and climate information. Nearly all states support stateclimate offices, which provide accurate and complete climatologic andweather data to everyone — local governments, residents, businesses,and agencies. Typically, state climate offices also provide the public withcost-effective services like hourly and daily data (including temperature,wind speed, dew point, barometric pressure, frost, and snowfall), climatemonitoring, applied climate research, and long-range forecasts andinterpretations of data, including "value-added" products tailored forusers and impact applications.Environmental/Social JusticeProviding the climate data proposedwill relieve the burden of dataassembly that is disproportionatelyheavy for small, rural, ordisadvantaged communities. Climatedata can also help us identify, engage,and address risks in disadvantagedcommunities.Although the University of Wisconsin-Madison has a Wisconsin StateClimatology Office, the office is the only one in the country to operate as apurely volunteer effort. The office receives no operational funding from any source and is led by two emeritusfaculty/staff members. The lack of ongoing support hinders Wisconsin’s ability to use relevant scientific informationand promote resiliency to climate change impacts in our communities.The Wisconsin State Climatology Office should also develop, maintain, and communicate a comprehensive databasedescribing present and future climate conditions for use by Wisconsin infrastructure planners, engineers, andpolicymakers. This work will include the creation of climate data sets for present and future conditions of criticalclimate variables such as rainfall, temperature, humidity, wind, snow, freeze/thaw and other variables. The data willbe presented in a consistent and easily accessible format. Critically, this effort will also identify state and municipalcodes and standards that should reference this newly developed data, and communicate the use and value of thedata by pilot infrastructure vulnerability and adaptive design demonstration projects for potable water, wastewater,public health, transportation, and water resources projects. Similar examples of the use of future climate data inpublic health and environmental assessments should be developed.To provide appropriate staffing and reliable climate information to the state, we suggest recognizing the StateClimatologist’s role in statute and funding a state climate office.For more background on this topic, please visit the Climate Working Group on the WICCI webpage.13

Wisconsin’s infrastructure is a source of greenhouse gases and vulnerable to climate impactsClimate impacts to Wisconsin’s infrastructure include more frequent andintense precipitation, higher annual precipitation amounts, earlierEnvironmental/Social Justicethawing in the spring and more freeze/thaw cycles combined with agreater number of rainy days, higher water table elevations, the potentialCommunities with lower tax basesfor higher lake levels, and more intense heat waves. The impact of theseoften do not have additional funds tochanges will increase vulnerabilities of our roads and rail systems inrepair or replace infrastructure withWisconsin, create public and environmental safety risks due to flooding,an eye toward climate resiliency. Incause a higher likelihood of bridge and dam failure, and result in damageaddition, infrastructure failures canto and inaccessibility of commercial ports and other coastal facilities.remove the only transportation routeMore roadway damage may lead to a reduction in commerce asfor emergency services, significantlycommunities face the possibilities of more weight limit restrictions onimpacting public health and safetynon-arterial roadways for a greater fraction of the year, difficultyduring extreme storm events.completing construction projects, and impacts to the traveling public andemergency vehicles. Guidance on the methodology of infrastructure riskassessment needs to be developed and publicized to reduce inefficient orinaccurate planning and expenditure due to uncertainty in climate change projections compounded with uncertaintyin vulnerability of specific infrastructure.Mitigating climate change impacts will require major changes to our energy and transportation infrastructure toreduce greenhouse gas emissions. In addition to the design challenges, funding mechanisms will need to be adjusted.For example, our transportation system is based on fossil fuels taxation, which is unsustainable in the long term andmakes it difficult to accelerate activities that support carbon-free energy sources. We suggest that revenue sourcesand financial planning be considered very early in the process of infrastructure greenhouse gas reduction efforts.Many construction materials and construction processes have high-embedded carbon content, resulting ingreenhouse gas emissions. Using lower carbon content materials, particularly in large projects, therefore representsan opportunity for meaningful climate change mitigation. We suggest that Wisconsin join the national trend towardsinfrastructure sustainability programs that encourage the use of sustainable materials, recycling, better planning, andmore efficient construction practices that incorporate reductions in carbon emissions from construction materials.These programs can also benefit the regional economy by encouraging locally sourced materials and spur technicaland business innovations. For such a program to be effective, however, it needs to establish unambiguous andtechnically sound guidelines, while providing simplicity and minimal burden for businesses to participate. Therefore, astudy is necessary to: (1) Review existing infrastructure sustainability programs adopted elsewhere in the U.S.; (2)Evaluate current levels of embodied carbon emissions in construction materials and processes in Wisconsin in orderto identify existing or potential mitigation strategies; (3) Develop practical and fair methods for evaluating andreporting embodied carbon emissions, considering the data available to state agencies and businesses; and (4)Investigate and suggest options to consider embodied carbon emissions in infrastructure project dev

Impacts (WICCI) and University of Wisconsin-Madison Nelson Institute for Environmental Studies to collect updated, impartial scientific data on the rate of climate change in Wisconsin and its impact on Wisconsin's natural environment. The WICCI is a statewide collaboration of scientists and