Banking Law and Insurance Climate Catastrophe Modeling in Spain

1. Introduction

Climate catastrophe modeling has become increasingly important for banks, insurers and financial regulators in Spain. Spain faces material physical risks from floods, droughts, wildfires, extreme heat, coastal events and severe storms. These events can damage insured property, reduce collateral values, interrupt businesses and increase insurance claims.

For banks, climate catastrophe modeling matters even though banks do not normally insure catastrophe risks themselves. Banks finance houses, commercial buildings, infrastructure, agriculture, businesses and projects that may be exposed to physical climate hazards. They may also lend to, invest in or otherwise have exposures to insurance companies.

Consequently, catastrophe losses can affect:

mortgage collateral;

borrowers' repayment capacity;

insurance availability;

insurance premiums;

corporate credit risk;

operational continuity;

property valuations;

investment portfolios;

insurer solvency; and

financial stability.

Spanish regulation must therefore be considered together with the wider European Union prudential, insurance and sustainability framework.

2. Meaning of Climate Catastrophe Modeling

A catastrophe model is a system used to estimate possible financial losses arising from severe events.

A simplified catastrophe model normally contains four major components:

Hazard Module

This estimates the probability and intensity of events such as floods, storms, droughts or wildfires.

Exposure Module

This identifies assets exposed to those hazards.

Examples include houses, factories, hotels, agricultural assets and infrastructure.

Vulnerability Module

This estimates how much damage a particular asset might suffer at different levels of hazard intensity.

Financial Module

This translates physical damage into financial losses after considering insurance limits, deductibles, reinsurance and other contractual arrangements.

For banks, the final results may also be translated into expected changes in collateral values, probability of default and loss given default.

3. Spanish Institutional Framework

Climate catastrophe risk in Spain involves several institutions.

The Banco de España supervises relevant aspects of the Spanish banking system and participates in the European Single Supervisory Mechanism.

The European Central Bank (ECB) directly supervises significant Spanish banking groups.

The Dirección General de Seguros y Fondos de Pensiones (DGSFP) is the principal Spanish insurance supervisory authority.

The Consorcio de Compensación de Seguros (CCS) plays a particularly important role because Spain has a statutory system for compensating certain extraordinary risks.

Therefore, catastrophe modeling in Spain exists at the intersection of banking supervision, insurance regulation, prudential risk management and public catastrophe-compensation arrangements.

4. Consorcio de Compensación de Seguros

Spain's catastrophe-insurance structure is unusual because the CCS provides compensation for specified extraordinary risks where the statutory conditions are satisfied.

Its framework is principally governed by the Legal Statute of the Consorcio de Compensación de Seguros and the Regulation on Extraordinary Risk Insurance.

Covered extraordinary natural phenomena include specified events such as:

extraordinary floods;

certain severe windstorms;

earthquakes;

seaquakes;

volcanic eruptions; and

falling astral bodies or aerolites.

Coverage depends on the statutory scheme and the existence of an eligible insurance policy carrying the relevant surcharge.

This institutional arrangement is extremely important when modeling catastrophe losses in Spain.

A model that assumes every catastrophe loss remains entirely with an ordinary private insurer may substantially misrepresent the Spanish system.

5. Importance for Banking Law

Banks have several reasons to understand insurance catastrophe risk.

Consider a bank with thousands of mortgages concentrated in a flood-prone region.

A severe event could simultaneously cause:

extensive property damage;

business interruption;

temporary unemployment or income loss;

falling property values;

increased borrower defaults; and

insurance and compensation claims.

The bank therefore needs to understand not only the probability of physical damage but also the extent to which insurance or the CCS could absorb losses.

Climate catastrophe modeling can consequently become part of prudent credit-risk and collateral management.

6. Physical Climate Risk

Physical climate risk is generally divided into acute and chronic risks.

Acute Physical Risk

Acute risks arise from particular extreme events, including:

floods;

wildfires;

severe storms; and

extreme heat episodes.

Chronic Physical Risk

Chronic risks develop over longer periods.

Examples include:

rising average temperatures;

persistent water scarcity;

desertification;

changing precipitation;

sea-level rise; and

long-term changes in agricultural productivity.

Catastrophe models traditionally concentrate on acute events, but modern financial risk analysis increasingly needs to consider both categories.

7. Transition Risk

Climate risk is not limited to physical disasters.

Banks and insurers can also face transition risk, meaning losses associated with the transition toward a lower-carbon economy.

Transition risks can result from:

new environmental regulation;

carbon pricing;

technological change;

changing consumer preferences;

litigation;

energy-efficiency requirements; and

declining values of carbon-intensive assets.

Catastrophe modeling and transition modeling are different exercises, but sophisticated climate-risk governance should consider both.

8. EU Banking Prudential Framework

Spanish banks operate under the EU prudential framework, including the Capital Requirements Regulation and Capital Requirements Directive regime.

Environmental, social and governance risks have increasingly become part of prudential supervision.

The European Banking Authority has developed requirements and guidance concerning ESG risk management, while the ECB expects significant institutions to identify, measure, manage and disclose climate-related and environmental risks.

Accordingly, a Spanish bank cannot reasonably treat physical climate exposure as completely separate from ordinary risk management.

Where climate events can materially affect credit, operational, market or other financial risks, they should be incorporated into the relevant risk-management processes.

9. ECB Climate Expectations

The ECB has developed supervisory expectations concerning climate-related and environmental risks.

These expectations address matters including:

business strategy;

governance;

risk appetite;

risk management;

reporting;

credit risk;

operational risk;

market risk;

scenario analysis; and

disclosure.

For significant Spanish banking institutions, this European supervisory framework is especially important.

Catastrophe modeling can help institutions satisfy these expectations by translating physical climate hazards into measurable financial exposures.

10. Insurance Regulation and Solvency II

Spanish insurers operate under the European Solvency II framework.

Solvency II requires insurers to hold capital appropriate to their risks and to maintain effective risk-management systems.

Catastrophe risk is particularly important for non-life insurers.

An insurer with large concentrations of property exposure can experience substantial simultaneous claims following a single event.

Solvency II therefore recognises catastrophe risk when determining solvency requirements.

For banks exposed to insurance companies, the financial resilience of insurers can consequently become relevant to counterparty and investment risk.

11. ORSA and Climate Risk

Insurers are required to conduct an Own Risk and Solvency Assessment (ORSA).

The ORSA enables an insurer to consider its particular risk profile rather than relying solely on standard regulatory formulas.

Climate change can alter the probability and severity of catastrophe losses.

An insurer may therefore need to consider whether historical assumptions remain appropriate.

Questions can include:

Are floods becoming more severe?

Are wildfires expanding geographically?

Is exposure increasing in vulnerable locations?

Are rebuilding costs increasing?

Are past catastrophe frequencies still reliable?

These issues make climate modeling an increasingly important component of forward-looking insurance governance.

12. Bank Stress Testing

Banks can use catastrophe scenarios to test their resilience.

For example, a hypothetical scenario might assume severe flooding across several Spanish regions.

The bank could estimate:

properties affected;

insured and uninsured losses;

CCS compensation;

reduction in collateral values;

borrower income disruption;

additional defaults;

expected credit losses; and

resulting impact on capital.

The purpose is not to predict precisely when a catastrophe will occur.

Stress testing instead asks:

What would happen to the institution if a severe but plausible event occurred?

13. Geographic Concentration Risk

Catastrophe risk is highly geographic.

Two banks with identical total mortgage portfolios can face very different physical risks if their loans are concentrated in different locations.

Relevant data may include:

flood zones;

wildfire exposure;

coastal vulnerability;

drought risk;

temperature;

building characteristics;

property use; and

insurance coverage.

Banks therefore increasingly need granular location information when assessing physical climate risk.

14. Insurance Protection and Credit Risk

Insurance can reduce the financial consequences of physical damage.

Suppose a mortgaged building is destroyed by an extraordinary flood.

Without adequate compensation, the borrower may owe a substantial mortgage on an asset that has lost much of its value.

Where insurance or the CCS compensates the loss, part of the economic damage may be absorbed.

Banks should therefore understand:

whether insurance exists;

what risks are covered;

exclusions;

deductibles;

policy limits;

extraordinary-risk arrangements; and

whether coverage is likely to remain available.

Insurance is therefore a relevant credit-risk mitigant, but it should not automatically be assumed to eliminate climate risk.

15. Insurance Protection Gap

A protection gap is the difference between total economic losses and losses actually covered by insurance or another compensation mechanism.

Climate change can enlarge this gap where:

losses become more frequent;

premiums rise;

insurers restrict coverage;

policyholders reduce coverage; or

particular risks become difficult to insure.

Spain's CCS framework can reduce parts of the catastrophe protection gap for risks falling within its statutory scope.

However, not every climate-related loss is automatically covered by the CCS.

Banks should therefore avoid assuming complete catastrophe protection.

16. Model Risk

Catastrophe models themselves create model risk.

A model may be inaccurate because of:

poor data;

incorrect assumptions;

outdated hazard maps;

inadequate climate projections;

inaccurate property information;

uncertain vulnerability functions; or

incorrect insurance assumptions.

Banks and insurers should therefore validate catastrophe models rather than treating model outputs as unquestionable facts.

Model governance should normally include:

independent validation;

documentation;

sensitivity testing;

data-quality controls;

periodic recalibration; and

management oversight.

17. Historical Data and Climate Change

Traditional catastrophe models often rely heavily on historical data.

Climate change creates a fundamental difficulty: the future may not statistically resemble the past.

A flood frequency estimated from twentieth-century data may become less reliable where precipitation patterns and land use have changed.

Consequently, modern models may combine:

historical observations;

scientific climate projections;

catastrophe simulations;

geographic information systems;

engineering vulnerability data; and

economic scenarios.

This creates uncertainty, but ignoring changing risk can create even larger modeling errors.

18. Governance Responsibilities

Climate catastrophe modeling should be integrated into institutional governance.

For banks, relevant functions may include:

Board of Directors

The board oversees material risk and establishes the institution's risk appetite.

Risk Management

Risk teams identify and quantify climate-related financial exposures.

Credit Function

Credit policies can incorporate climate effects on borrowers and collateral.

Model Risk Function

Models should be validated and challenged.

Internal Audit

Internal audit can examine whether climate-risk controls operate effectively.

Compliance

Compliance helps ensure that regulatory and disclosure obligations are satisfied.

Climate modeling should therefore not remain solely within a technical sustainability department.

19. Important Case Law

There are relatively few judgments specifically addressing bank catastrophe models. The relevant jurisprudence instead establishes principles concerning climate responsibility, environmental liability, insurance compensation, catastrophe classification and financial disclosure.

Case 1 — Armando Carvalho and Others v European Parliament and Council, T-330/18

This case became widely known as the People's Climate Case.

Individuals and families affected by climate change challenged EU climate legislation and sought stronger emissions reductions.

The General Court dismissed the action on standing grounds.

Relevance

Although it was not a banking case, the litigation demonstrates that climate-related damage can generate legal claims and litigation risk.

For banks and insurers, litigation risk can become part of the broader financial consequences of climate change.

The case also illustrates the procedural difficulty of establishing standing in broad climate litigation.

20. Case 2 — Carvalho and Others v Parliament and Council, C-565/19 P

The applicants appealed the General Court's decision.

The Court of Justice dismissed the appeal.

Importance

The decision confirmed the restrictive EU standing requirements applicable to private applicants challenging generally applicable EU measures.

Financial-sector relevance

Climate litigation may arise through different legal routes, including:

regulatory challenges;

corporate litigation;

disclosure disputes;

damages claims; and

insurance disputes.

Banks and insurers therefore need to consider litigation as one component of climate-related financial risk.

21. Case 3 — ClientEarth v European Investment Bank, C-212/21 P

This important environmental-law case concerned the EIB's decision relating to financing of a biomass power project.

The Court of Justice addressed access to environmental review mechanisms.

Banking relevance

The case is significant because it connects financial decision-making and environmental law.

It demonstrates that financing decisions concerning environmentally significant projects can become subject to environmental legal scrutiny.

For Spanish banks financing major projects, environmental and climate considerations can therefore have consequences beyond traditional credit analysis.

22. Case 4 — Bankwatch Network v European Commission, T-307/16

This General Court litigation concerned access to environmental information connected with financing activities involving the European Investment Bank.

Importance

The case illustrates the relationship between financial institutions, environmental information and transparency.

Climate-model relevance

Catastrophe and climate-risk models depend heavily upon environmental information.

Questions concerning the quality, availability and disclosure of environmental data therefore have direct significance for financial risk assessment.

23. Case 5 — Association France Nature Environnement v Premier ministre, C-379/15

The CJEU considered environmental-law obligations and the circumstances surrounding compliance with EU environmental requirements.

Although the case was not about banking or insurance, it demonstrates the strict legal significance of EU environmental obligations.

Relevance to financial institutions

Environmental regulation can affect:

asset values;

industrial operations;

project viability;

borrower costs; and

insurance liabilities.

These effects can ultimately become credit or underwriting risks.

Environmental-law developments therefore form part of the external legal environment that climate financial models may need to consider.

24. Case 6 — Folk v Unabhängiger Verwaltungssenat für die Steiermark, C-529/15

The CJEU considered environmental liability under the Environmental Liability Directive.

The case concerned environmental damage associated with the operation of a hydroelectric power plant.

Importance

Environmental damage can create remediation obligations and financial liabilities.

Banking relevance

Where a bank finances an environmentally sensitive company or project, environmental liabilities can weaken the borrower's financial position.

For insurers, those liabilities may also raise questions concerning policy coverage.

Thus, catastrophe modeling should sometimes be considered alongside environmental-liability modeling.

25. Case 7 — Föreningen Greenpeace Norden v European Commission, C-673/13 P

This litigation involved environmental information and transparency concerning EU decision-making.

Relevance

Climate and catastrophe risk management depends heavily on reliable environmental information.

The broader principle demonstrated by EU environmental jurisprudence is that environmental data can have substantial public-law significance.

Financial institutions increasingly depend upon similar information when estimating physical climate exposure.

26. Case 8 — Allianz IARD and Others, C-307/19

This CJEU litigation concerned insurance arrangements and the interpretation of EU insurance-related rules.

Although it was not a climate catastrophe-modeling case, it demonstrates the importance of harmonised EU principles in determining insurance rights and obligations.

Relevance to Spain

Spanish catastrophe-risk management operates inside the broader EU insurance-law framework.

Insurance-model assumptions must therefore reflect legal coverage structures rather than merely physical loss estimates.

A catastrophe model that accurately predicts physical damage but incorrectly models insurance obligations can still produce a materially incorrect financial-loss estimate.

27. Spanish Catastrophe Compensation Litigation

Spanish courts have also dealt with disputes involving the Consorcio de Compensación de Seguros, particularly questions concerning extraordinary risks, insurance coverage and entitlement to compensation.

These disputes are particularly important for catastrophe modeling because the legal classification of an event can determine who ultimately bears the financial loss.

A model should therefore distinguish among:

total physical loss;

ordinary insurer liability;

CCS-covered extraordinary loss;

policyholder retention; and

uninsured loss.

This distinction is essential for accurate Spanish catastrophe-risk analysis.

28. The 2024 Valencia Floods as a Risk Illustration

The catastrophic flooding associated with the October 2024 DANA event, particularly in Valencia, provides a major practical illustration of catastrophe risk in Spain.

The event generated extensive damage to homes, vehicles, businesses and infrastructure and triggered a very large volume of compensation claims.

From a financial-risk perspective, such an event demonstrates why catastrophe models must consider simultaneous effects across:

households;

SMEs;

property;

vehicles;

infrastructure;

insurers;

banks; and

public compensation mechanisms.

A bank exposed to thousands of borrowers in one affected geographic area may experience correlated credit deterioration even when individual loans initially appeared diversified.

29. Correlation Risk

Catastrophes create unusually high correlation.

Ordinary credit models may assume that borrowers fail for relatively independent reasons.

A climate catastrophe can affect thousands of borrowers simultaneously.

For example:

Flood → property damage → business interruption → reduced household income → borrower defaults → declining collateral values.

The same event can therefore affect both sides of a mortgage-risk calculation:

probability of default increases; and

recovery value decreases.

This is why geographic catastrophe modeling can provide information that traditional borrower-level credit scoring may miss.

30. Reinsurance

Reinsurance allows insurers to transfer part of their risk to other insurers.

It is particularly important for catastrophe exposure because one major event can produce thousands of claims simultaneously.

Banks evaluating insurance-sector counterparties should therefore understand whether an insurer has adequate:

reinsurance;

capital;

catastrophe reserves;

geographic diversification; and

liquidity.

However, reinsurance creates counterparty risk because the insurer depends on the reinsurer's ability to perform.

31. Climate Scenario Analysis

Catastrophe modeling can be combined with longer-term climate scenarios.

A bank could examine its mortgage portfolio under scenarios involving:

higher temperatures;

increasing flood frequency;

prolonged drought;

wildfire expansion;

coastal flooding; and

changes in insurance availability.

The analysis can then estimate changes in:

expected credit losses;

collateral values;

defaults;

capital requirements; and

profitability.

Scenario analysis should generally be interpreted as a risk-management exercise rather than a precise prediction of future climate conditions.

32. Data Protection and Modeling

Climate models can use highly granular information concerning properties and borrowers.

Banks should therefore consider data-protection requirements when processing personal data.

Where models combine:

addresses;

property characteristics;

mortgage information;

financial circumstances; and

geographic hazard data,

the institution must ensure that personal-data processing has an appropriate legal basis and satisfies applicable data-protection requirements.

Climate-risk management does not automatically override privacy law.

33. Climate Disclosure

Climate-risk information is increasingly relevant to financial disclosure.

Investors may want to understand:

exposure to physical risks;

geographic concentrations;

scenario-analysis results;

transition risks;

risk-management arrangements; and

material financial effects.

Inaccurate climate statements can potentially create legal and reputational risks.

Institutions should therefore avoid both understating climate exposure and making unsupported environmental claims.

34. Catastrophe Modeling and Mortgages

Mortgage lending provides a straightforward example.

Before granting a long-term mortgage, a bank traditionally considers:

borrower income;

credit history;

loan-to-value ratio;

interest rates; and

property valuation.

Climate risk adds another dimension.

A property may have a good present valuation but face increasing flood, wildfire or coastal risk during a 20- or 30-year mortgage.

The bank may therefore need to consider how physical risk could affect future collateral value and borrower resilience.

35. Catastrophe Modeling and Corporate Lending

Corporate borrowers can also face significant climate exposure.

A hotel may depend on coastal infrastructure.

A manufacturer may depend on reliable water supplies.

An agricultural company may be vulnerable to drought.

A logistics company may depend on infrastructure exposed to flooding.

Climate catastrophe modeling can therefore support sector-specific credit analysis rather than being restricted to residential mortgages.

36. Regulatory Inspection

Supervisors can examine whether climate risk has been properly incorporated into governance and risk-management systems.

Potential areas of supervisory review include:

risk identification;

data quality;

modeling methodologies;

stress testing;

board reporting;

scenario analysis;

internal controls;

disclosure; and

remediation of identified weaknesses.

A bank does not necessarily satisfy supervisory expectations simply because it has purchased a sophisticated external catastrophe model.

Management must understand its limitations and integrate relevant results into actual decision-making.

37. Practical Example

Suppose a Spanish bank has €8 billion of mortgages concentrated across Mediterranean coastal regions.

Its catastrophe model estimates increased exposure to severe flooding over the life of the loans.

The bank should not simply conclude that every projected physical loss becomes a credit loss.

It should examine:

Step 1 — Hazard

Which properties are exposed?

Step 2 — Vulnerability

How badly could those properties be damaged?

Step 3 — Insurance

What ordinary insurance coverage exists?

Step 4 — CCS

Which extraordinary losses could fall within the CCS regime?

Step 5 — Borrower Impact

Would borrowers experience income disruption despite compensation?

Step 6 — Collateral

Could long-term property values decline?

Step 7 — Credit Risk

How would probability of default and loss given default change?

Step 8 — Capital

Would the resulting losses materially affect the bank's capital position?

This produces a much more realistic financial assessment than simply estimating physical damage.

38. Key Legal Principles from the Cases

The relevant jurisprudence supports several broader principles.

Carvalho v Parliament and Council illustrates climate litigation and the strict requirements governing standing before EU courts.

Carvalho, C-565/19 P confirms those procedural principles at appellate level.

ClientEarth v EIB demonstrates that environmental law can directly interact with institutional financing decisions.

Bankwatch Network v Commission highlights the significance of environmental information surrounding financial activities.

France Nature Environnement demonstrates the legal significance of compliance with EU environmental obligations.

Folk illustrates how environmental damage can generate legal liability capable of producing financial consequences.

Greenpeace Norden reinforces the significance of environmental information and transparency.

Insurance-related jurisprudence further demonstrates that financial modeling must account for legal insurance structures rather than considering physical damage alone.

39. Limits of Catastrophe Models

No catastrophe model can eliminate uncertainty.

Models cannot perfectly predict:

the exact location of the next flood;

when a wildfire will occur;

future climate policy;

future property values;

future insurance premiums; or

individual borrower behaviour.

Model outputs should therefore be expressed as estimates, ranges or scenarios where appropriate.

A governance failure can occur if management treats uncertain projections as guaranteed outcomes.

Equally, uncertainty is not a sound reason to ignore a material risk.

40. Relationship Between Banking and Insurance

Climate catastrophes demonstrate how closely banking and insurance are connected.

A severe event can produce the following chain:

Climate event → physical damage → insurance claim → CCS/reinsurance response → borrower financial stress → collateral impairment → bank credit losses → prudential consequences.

Each stage is governed by different legal rules.

Effective catastrophe modeling therefore requires collaboration among:

bankers;

insurers;

actuaries;

climate scientists;

engineers;

lawyers;

economists; and

risk managers.

41. Conclusion

Banking law and insurance climate catastrophe modeling in Spain form an increasingly important area of financial-risk management.

Spain's exposure to floods, wildfires, droughts, extreme temperatures and other physical hazards means climate risk can affect banks through borrowers, collateral, insurance counterparties, investment portfolios and operational disruption.

The Spanish framework has an additional distinctive feature: the Consorcio de Compensación de Seguros, which provides compensation for specified extraordinary risks under statutory conditions. Any serious Spanish catastrophe model must therefore distinguish between physical economic loss, private insurance liability, CCS compensation and residual uninsured loss.

At European level, the ECB prudential framework, EU banking legislation and Solvency II increasingly require banks and insurers to approach environmental and climate risks through governance, risk management, stress testing, scenario analysis and forward-looking solvency assessment.

The jurisprudence—including Carvalho, ClientEarth v EIB, Bankwatch Network, France Nature Environnement, Folk and Greenpeace Norden, together with insurance and Spanish CCS jurisprudence—shows that climate-related financial risk cannot be separated entirely from environmental law, liability, disclosure and insurance coverage.

The central banking-law principle is therefore that climate catastrophe modeling should convert physical environmental hazards into measurable financial risks without treating uncertain model outputs as certain predictions.

For Spanish banks, an effective framework should connect:

climate hazard → asset exposure → physical vulnerability → insurance/CCS protection → borrower impact → collateral impairment → credit loss → capital and liquidity consequences.

Used properly, catastrophe modeling is therefore not merely an insurance technique. It is an increasingly important component of banking governance, prudential risk management, financial resilience and long-term credit assessment in Spain.