Cumulative exposure to climate change

More instances of what we at the Strategic Climate Risks Initiative call ‘derailment risk’: the threat of climate consequences getting in the way of climate action - this time in a pre-print academic paper: “There is concern that climate change, through its economic impacts, may lock countries into a “vicious cycle” in which mounting economic losses further constrain countries’ capacity to invest in adaptation and mitigation. We provide evidence that the cost and availability of capital for many countries have already been shaped by their historical exposure to tropical cyclones (TCs) and warming temperatures. Our empirically derived estimates suggest that, across all TC-exposed countries, debt-to-GDP ratios are on average 30% higher due to the cu-mulative effects of TCs since 1990. GDP levels are on average 10% lower due to the combinedimpacts of TCs and warming temperatures across all countries. We estimate that because ofthese impacts, hotter countries are more likely to receive credit ratings below investment grade(< BBB–), and borrowing costs are at least 1 basis point (0.01%) higher in 28 countries and 5 basis points higher in highly-exposed countries. Future increases in temperature and TC activity will likely worsen countries’ credit, potentially undermining both countries’ abilities toaddress climate change and their long-run development prospects.” https://lnkd.in/erjeac75

Even as we go through record heatwaves, climate still feels like a distant problem somehow. That's the contradiction: we experience extreme heat, adapt our behavior for a few days, then default back to treating climate as something that happens later, somewhere else. We see unusual events as anomalies instead of recognizing the pattern. R. Jisung Park's research explains what we're missing: catastrophic hurricanes aren't driving the most damage; unremarkably hot days are. Days around 27-32°C cause just as many excess deaths as record heatwaves. A 32°C day increases workplace injury risk by 65%. Students who took exams on 32°C days were 10% less likely to pass. These are small, compounding changes barely noticeable in any given year. But cumulatively, they reshape productivity, health, learning, and economic performance. Park estimates wildfire smoke could cause 20,000+ additional deaths per year by 2050. Most won't be categorized as wildfire deaths because they result from cumulative air quality degradation over weeks and months. The investment problem: we don't see what's in front of us. Capital stays focused on 2100 projections while demand accumulates today. But the companies solving heat stress, air quality, water scarcity, and infrastructure fragility are selling into current needs that compound every year. What should change: 📝 Track cumulative impacts, not just catastrophes. Moderately elevated temperatures create larger aggregate costs through productivity loss and health impacts than billion-dollar disasters. 🌡️ Reframe climate as present-day demand. Heat-related workplace injuries drive demand for cooling wearables now. Declining student performance drives demand for efficient HVAC now. Wildfire smoke drives demand for air filtration now. 💵 Allocate to adaptation intentionally. If you invest in infrastructure, healthcare, or industrials, adaptation opportunities are embedded. Isolate companies whose revenue grows as conditions worsen. The March heatwave is right in front of us. The demand is here. The question is whether we'll keep treating it as an anomaly or start investing in what's already happening. Link to the opinion piece in first comment.

A new study, supported by the European Union’s Horizon research and innovation programme, shows that the climate impacts we often associate with the distant future — from water stress to crop failures and heat extremes — are already emerging across multiple sectors. By applying the concept of Time of Emergence (TOE), the study identifies when climate-related changes become statistically distinct from historical variability. The results are striking: In many regions, TOE occurred before 2020 for several key indicators. 👉Tropical areas face the greatest burden of early and compounding stressors, 👉including rising heat extremes and declining crop yields. 👉In contrast, northern latitudes may experience beneficial changes, such as increased agricultural productivity — highlighting a deepening inequality in climate impacts. These cumulative shifts, both positive and negative, are projected to peak before 2050. For anyone working in foresight, policy, resilience, or sustainability, this is a crucial reminder: The future is already underway — and its effects are not evenly distributed. #Foresight #StrategicPlanning #ClimateJustice #FutureStudies

Climate exposure is rapidly becoming a core determinant of sovereign and corporate creditworthiness. Macro-financial analysis from the University of Cambridge and others shows that without decisive mitigation, climate impacts could begin to erode sovereign credit ratings within five years raising borrowing costs for governments and, by extension, businesses. Over time, the economic drag could reach double-digit GDP losses, driven not by capital destruction alone but by a sustained fall in productivity and output. This reshapes fiscal and monetary policy fundamentals. Climate risk is now a structural factor in debt sustainability, cost of capital, and financial stability. The risk is no longer distant or diffuse, it’s embedded in the credit system itself. The cost of inaction was a central theme in my UK meetings in June, particularly discussing the research by Kamiar Mohaddes and others at Cambridge Judge Business School where the connection between climate credibility and economic credibility was unmistakably clear. For policymakers and investors alike, the question is shifting from “what is the cost of action?” to “what is the credit cost of inaction?” Photos from my visit with the team at Cambridge #macroeconomics #climaterisk #fiscalpolicy #climatechange

Wildfire smoke and extreme heat aren’t just environmental issues—they’re now major drivers of disease across the U.S., and a new actuarial analysis by Milliman, Rong Yi, Meseret Woldeyes, M.S., and Garrett Bradford puts numbers to what many of us in health care have been seeing firsthand. The report finds that the combined impacts of wildfire PM2.5 and extreme heat account for 2.3% to 8.6% of all disease prevalence across Medicaid, Medicare, and commercially insured populations. That’s 26% to 56% of the total environmental and socio-contextual influence on health—a magnitude "that rivals, and often exceeds, the health impact of the COVID-19 pandemic and its aftermath." What’s even more striking is how these impacts unfold over time: 🔥 First 4 months: Respiratory disease spikes immediately in commercial and Medicaid populations. Medicaid enrollees also see early increases in mental and behavioral health conditions—likely acute stress responses to smoke and environmental instability. 🔥 4–8 months: Cardiovascular disease begins rising across all insurance groups, reflecting the systemic inflammation and oxidative stress triggered by prolonged PM2.5 exposure. Mental and behavioral health impacts continue to build. 🔥 8–12+ months: Medicare beneficiaries experience cumulative, long-term effects—including rising cardiovascular disease, neurocognitive and psychiatric conditions, and even neoplasms—consistent with research linking chronic air pollution to dementia and neurodegeneration. These findings underscore a simple truth: wildfires and extreme heat are reshaping the nation’s health burden in ways we can no longer ignore. Protecting people means investing in clean indoor air, strengthening public health systems, and—most importantly—accelerating the transition away from fossil fuels that drive these crises. Read the full report here: https://lnkd.in/gjFnRQdt

Cumulative carbon emissions (CE) reflect the total CO₂ released by human activity over time, and they serve as a critical metric for understanding climate change. Contrary to annual emissions, CE captures the long-term legacy of fossil fuel use and land-use change. Scientific evidence shows a near-linear relationship between CE and observable climate impacts, rising global temperatures, sea level rise, extreme heat events, and ocean acidification. This relationship, known as the transient climate response to cumulative emissions, enables policymakers to link each tonne of CO₂ to tangible ecological and societal consequences. It also forms the basis of the carbon budget, translating temperature goals into actionable emission limits. Cumulative emissions reframes climate action as an urgent, measurable, and consequential choice where every tonne counts. Rooted in scientific evidence, CE emphasise clarity over alarm, it’s a metric that makes the stakes visible, the choices measurable, and the urgency rational. Image: Solid lines with dots reproduce the globally averaged near-surface air temperature response to cumulative CO2 emissions plus non-CO2 forcers.https://https://lnkd.in/eGayc4An Claude-Michel Nzotungicimpaye and H Damon Matthews (2024). Linking cumulative carbon emissions to observable climate impacts. Environ. Res.: Climate 3 032001 DOI 10.1088/2752-5295/ad3fda https://lnkd.in/eygww4ti

Blue carbon ecosystems don’t experience threats one at a time. They experience them together. Climate change. Land-use pressure. Hydrological alteration. Local disturbance. In a new study led by Nipuni Perera, we mapped the future cumulative exposure of #BlueCarbon ecosystems to multiple stressors under different scenarios. The results show: • Overlapping stressors are spatially clustered rather than evenly distributed • Exposure to multiple pressures increases under higher emissions pathways • Some regions emerge as potential future hotspots of compound exposure • Others remain comparatively lower exposure — highlighting opportunities for strategic protection ➡️ The implication: prioritisation needs to account for cumulative exposure, not just carbon stocks or current condition. Congratulations to Nipuni Perera who led this work as part of her PhD within the RMIT Centre for Nature Positive Solutions (and BlueCarbonLab). Developing spatial modelling, scenario analysis and cumulative risk frameworks is exactly what doctoral training should be about — building the tools to answer complex, real-world questions. And this is thanks to a really supportive supervisory/co-author team who provide this training: Micheli Costa, Melissa Wartman, and Martino E. Malerba. Proud to see this contribution adding rigour to how we think about blue carbon futures. 🔗Article Link: https://lnkd.in/gGCAAJ7c