Climate Risk Guide — Physical and Transition Risks Explained
Climate risk splits into physical risks from extreme weather and chronic climate shifts, and transition risks from policy, technology, and market changes as the world decarbonizes. Investors must assess both to protect portfolio value.
Physical climate risk includes acute events like hurricanes, wildfires, floods, and heatwaves that damage physical assets and disrupt supply chains. Hurricane Katrina caused $125 billion in damages; Hurricane Harvey damaged $100 billion in real estate and infrastructure. Wildfires in California destroyed over $40 billion in property. Chronic physical risks such as sea level rise, temperature increases, and water scarcity erode asset values over decades. Miami Beach spends $500 million on sea-level adaptation. Agricultural regions shift as temperatures rise — California's Central Valley faces water shortages that reduce crop yields.
Transition risk arises from the shift to a net-zero economy. Policy risks include carbon pricing (EU ETS at €80+ per ton), emissions regulations, and fuel economy standards. Technology risks emerge as renewables outcompete fossil fuels — solar and wind are now cheaper than coal in most markets. Legal risks grow as climate litigation increases; Shell was ordered to cut emissions 45% by 2030 in a Dutch court ruling. Reputation risks drive divestment — fossil fuel companies face pressure from institutional investors managing $50 trillion in committed net-zero assets.
Assessing and Managing Climate Risk in Portfolios
Investors assess climate risk through carbon footprinting, scenario analysis, and climate value at risk (VaR) metrics. The four most common climate scenarios from the Network for Greening the Financial System (NGFS) are: Net Zero 2050 (stringent policy limits warming to 1.5°C), Divergent Net Zero (delayed action requiring rapid change), Nationally Determined Contributions (current pledges achieved, ~2.5°C warming), and Current Policies (no additional policy, ~3°C+ warming). Portfolio managers use these scenarios to stress-test holdings for stranded asset risk, revenue exposure, and valuation impacts. Managing climate risk involves reducing exposure to high-carbon sectors, increasing allocation to climate solutions, engaging portfolio companies, and using climate-aligned benchmarks like the EU Paris-Aligned Benchmark.
FAQs
What is the difference between physical and transition climate risk?
Physical risk comes from climate change impacts like storms, floods, heatwaves, and sea-level rise. Transition risk comes from the process of adjusting to a low-carbon economy, including regulatory changes, technological disruption, and shifting market preferences. Both affect portfolio returns.
What is stranded asset risk?
Stranded asset risk is the risk that fossil fuel reserves and carbon-intensive infrastructure become economically unviable before the end of their useful life. Estimates suggest 60-80% of known fossil fuel reserves cannot be burned under a 1.5°C warming limit. Coal power plants, oil sands, and Arctic drilling projects are particularly vulnerable.
How do investors measure climate risk exposure?
Common metrics include weighted average carbon intensity (WACI), carbon footprint (tons CO2e per $M invested), fossil fuel exposure percentage, and climate value at risk. Data providers like MSCI, Sustainalytics, and S&P Trucost offer portfolio-level climate analytics. Scenario analysis tools from Carbon Tracker and NGFS help model outcomes.