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BIS Working Paper Summary: Supply Chain Transmission of Climate-Related Physical Risks

Authors: Douglas K.G. Araujo, Fernando Linardi, Luis Vissotto
Affiliation: Bank for International Settlements (BIS) & Banco Central do Brasil
Date: April 2025
JEL Codes: E32, L14, Q54, R15
Keywords: Climate-related physical risks, Precipitation anomalies, Supply chains, GDP growth

1. Background & Objectives

• Climate-related physical risks (e.g., droughts, floods) disproportionately affect economic activity in low-income regions.
• Previous research often focused only on extreme events, ignoring moderate shocks.
• Objective: Evaluate the impact of precipitation anomalies (dry/wet spells) of varying intensities (moderate vs. intense) on local and remote economic activities in Brazil.

2. Data & Methodology

• Data Sources:

  • Climate Data: Municipality-level precipitation/temperature (CRU TS dataset) used to compute the Standardized Precipitation Evapotranspiration Index (SPEI).
  • Supply Chain Data: Confidential BCB firm-to-firm electronic payment transactions reflecting trade links.
  • Economic Data: Subnational GDP (agriculture, manufacturing, services); foreign trade metrics.

• Key Variables:

  • Dependent: Municipality GDP growth (annual).
  • Independent: Local and remote climate anomalies (SPEI-based), sectoral breakdowns, supply chain networks.
  • Controls: Lagged GDP, pre-shock climate conditions, fixed effects for municipalities and years.

• Analysis Framework:

  • Econometric regressions estimating effects of moderate vs. intense precipitation anomalies on GDP growth.
  • Supply chain extensions: Assess impacts of customer/supplier climate shocks (separated by distance to mitigate spurious correlation).
  • Sectoral analysis: Breakdown for agriculture, manufacturing, and services.
  • Counterfactuals: Simulate climate change contribution to GDP losses by projecting counterfactual SPEI trends.

3. Key Findings

3.1 Local Economic Effects

• Short-term Impact:

  • Dry spells reduce GDP growth by ~1–2 percentage points (p.p.).
  • Wet spells have a smaller but statistically significant negative effect (e.g., ~0.5–1 p.p.).
  • Moderate shocks explain ~90% of negative economic effects, outweighing intense events.

• Sectoral Differences:

  • Agriculture: Most sensitive to dry spells (e.g., ~3.8 p.p. for intense shocks).
  • Manufacturing: Less responsive but highly affected by intense supplier shocks.
  • Services: Less affected by climate at scale but shows localized adjustments.

3.2 Supply Chain Transmission

• Effect Size:

  • A dry spell in a customer municipality reduces local GDP by ~1–2 p.p.
  • Effects dilute with distance, reflecting moderate shock prevalence.

• Transmission Mechanisms:

  • Spillovers reduce import growth and labor market metrics (e.g., payroll reduction).
  • No evidence that foreign trade offsets domestic supply chain shocks.

• Sectoral Heterogeneity:

  • Agriculture is highly affected by both local and remote climate shocks.
  • Manufacturing amplifies only intense supplier shocks.
  • Services show little evidence of remote shock transmission.

3.3 Climate Change Contribution to GDP Losses

• Counterfactual estimates show that supply chain spillovers explain up to 1 percentage point of annual GDP growth losses attributed to climate change.
• Ignoring supply chain effects underestimates total climate-related economic damage.

4. Policy Implications

• Climate policies should account for:
  1. Non-extreme events: Focus on adaptation to moderate droughts and floods.
  2. Sectoral risks: Target financial/labor reallocation in high-vulnerability sectors like agriculture.
  3. Supply chain resilience: Encourage diversification in trade relationships to mitigate spillovers.

5. Supporting Tables

Table: Economic Effects of Local Dry Spells

Table: GDP Growth from Supply Chain Shocks

References

• Araujo et al. (2025). Supply chain transmission of climate-related physical risks. BIS WP 1260.
• Burke et al. (2015). Global non-linear effects of temperature on economic production. Nature.
• Zappala (2023). Sectoral impact and propagation of weather shocks. IMF Working Paper.