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The Data Wars

The Climate Data That Disappeared Without Anyone Changing the Rules

By Ivy Marlowe— February 16, 2026

Feature image for article: The Climate Data That Disappeared Without Anyone Changing the Rules

In November 2025, climate risk information vanished from California property listings on Zillow. Wildfire exposure, flood projections, heat risk, air quality—gone. The data remained public, still accessible through government databases. Where homebuyers actually search, though, it disappeared. No new regulations required this. No rules changed. Someone decided you shouldn't see it there anymore. And when that happened, someone else started building a workaround to restore what was always public in the first place.

The Data Wars

The Climate Data That Disappeared Without Anyone Changing the Rules

By Ivy Marlowe— February 16, 2026

In November 2025, climate risk information vanished from California property listings on Zillow. Wildfire exposure, flood projections, heat risk, air quality—gone. The data remained public, still accessible through government databases. Where homebuyers actually search, though, it disappeared. No new regulations required this. No rules changed. Someone decided you shouldn't see it there anymore. And when that happened, someone else started building a workaround to restore what was always public in the first place.

What Disappeared

When Zillow Hid the Flood Maps

Until November 14, 2025, every Zillow listing showed property-specific climate scores: flood probability, wildfire risk, wind exposure, heat projections, air quality ratings. Fifteen and thirty years out. Then California's largest MLS complained that flood models showed 50% risk in neighborhoods that hadn't flooded in decades. Zillow pulled everything.

The data still exists, buried behind links most buyers won't find. What disappeared was the automatic display. Homes with high flood risk sold at 52% compared to 71% for low-risk properties, according to Zillow's own analysis. Real estate agents told the company the scores were killing deals. Zillow listened to the agents.

What Disappeared

When Zillow Hid the Flood Maps

Until November 14, 2025, every Zillow listing showed property-specific climate scores: flood probability, wildfire risk, wind exposure, heat projections, air quality ratings. Fifteen and thirty years out. Then California's largest MLS complained that flood models showed 50% risk in neighborhoods that hadn't flooded in decades. Zillow pulled everything.

The data still exists, buried behind links most buyers won't find. What disappeared was the automatic display. Homes with high flood risk sold at 52% compared to 71% for low-risk properties, according to Zillow's own analysis. Real estate agents told the company the scores were killing deals. Zillow listened to the agents.

TAKE NOTE

Competing platforms: Redfin and Realtor.com still display First Street climate data prominently on listings, though Redfin lets sellers request removal if scores seem wrong.

What remains: Neighborhood-level risk maps requiring extra clicks, but no property-specific scores or insurance recommendations that previously appeared automatically on every listing page.

Model defense: First Street noted its wildfire risk scores identified over 90% of Los Angeles homes that burned in recent fires as severe risk zones.

Disclosure vacuum: Most states don't require sellers to reveal recent flooding or wildfire vulnerability, making third-party climate data essential for informed buying decisions.

Buyer behavior: Redfin experiment found buyers who saw flood risk scores made offers on homes with 50% less risk than those who didn't see the data.

Measuring Risk

Pull up your flood risk on three different platforms. You might get three wildly different answers. One says you're clear. Another puts you in a high-risk zone. The third suggests your insurance company has been underpricing your policy for years, and they're about to correct that mistake.

The divergence exists because these platforms measure fundamentally different things using different data sources and timeframes. Some look backward at what flooded before. Others project forward using climate models that disagree with each other. The confusion matters because homeowners trying to make real decisions about real money get contradictory information, and insurance premiums can triple overnight when carriers switch which model they trust.

Measuring Risk

Pull up your flood risk on three different platforms. You might get three wildly different answers. One says you're clear. Another puts you in a high-risk zone. The third suggests your insurance company has been underpricing your policy for years, and they're about to correct that mistake.

The divergence exists because these platforms measure fundamentally different things using different data sources and timeframes. Some look backward at what flooded before. Others project forward using climate models that disagree with each other. The confusion matters because homeowners trying to make real decisions about real money get contradictory information, and insurance premiums can triple overnight when carriers switch which model they trust.

Forward Projections

First Street Bets on Tomorrow

First Street runs CMIP6 climate projections forward thirty years, layering sea level rise and rainfall pattern shifts onto property-level flood models. Each address gets a Flood Factor score based on cumulative future risk, not what happened last decade.

Historical Data

FEMA Maps What Already Happened

FEMA flood maps use historical flow data, period. No climate adjustments, no forward modeling. Some maps date to the 1970s because Congress won't fund adequate updates. They're regulatory snapshots for insurance pricing, frozen at whatever conditions existed when surveyors last showed up.

Risk Gap

Six Million Properties FEMA Missed

First Street counts 14.6 million at-risk properties nationwide. FEMA counts 8.7 million. In Kentucky's Appalachian counties alone, that's 22,086 properties versus 6,562. The gap means millions of homeowners are underestimating their exposure because the official maps say they're fine.

Insurance Pricing

Proprietary Models Set Your Premium

Insurance companies run their own catastrophe models using IPCC scenarios but rarely publish methodology details. Most do "exploratory" analysis of possible futures without stress testing worst cases. Premium calculations vary wildly depending on whether carriers use FEMA's outdated maps or fully risk-based assessments.