The Climate Data That Disappeared Without Anyone Changing the Rules

In mid-November 2025, climate risk information vanished from California property listings on Zillow. Not just flood risk—wildfire exposure, extreme heat projections, air quality data, wind risk. All of it. The platform that had added climate scores to listings just a year earlier now offered only a small hyperlink, easy to miss, directing users elsewhere to find what used to be right there.

Neil Matouka, who previously managed California's Fifth Climate Change Assessment, noticed the void and started building a workaround. His browser plugin pulls from the same publicly available sources—CAL FIRE fire hazard zones, FEMA flood data, Cal-Adapt climate projections—and displays them below the property price when you view a California listing on Zillow. The information was always accessible. Someone decided to stop showing it.

The plugin is explicitly framed as "a proof of concept and should not be relied upon to make purchasing decisions." But the fact that it exists at all raises the real question: how does climate risk information actually reach homebuyers, and who controls whether it does?

What Changed (And What Didn't)

CRMLS stated this when asked if MLS standards had been updated. Yet Zillow cited the need to "adhere to varying MLS requirements" as justification for removing all climate data from every listing nationwide.

CRMLS questioned the data while maintaining its standards unchanged. Zillow responded to that pressure by removing everything.

Accuracy concerns from California Regional Multiple Listing Service, one of the nation's largest MLS systems, triggered the removal. CRMLS CEO Art Carter pointed to flood modeling showing neighborhoods with 50% probability of flooding this year—in areas that hadn't flooded in 40 or 50 years. Fair question about model accuracy.

Zillow's response reveals how information control actually works. The platform removed all climate risk information—flood, fire, wind, heat, air quality—from every listing nationwide. A California-specific accuracy concern became a nationwide information removal.

Redfin, Realtor.com, and Homes.com continue displaying the same First Street Foundation data that Zillow removed. Same data provider, same accuracy questions, different platform responses. Whose concerns mattered here?

The Infrastructure Nobody Sees

Multiple Listing Services are private databases created by real estate professionals to share listings. Platforms like Zillow pull data from various regional MLS systems. But the MLS systems control what flows through, and their concerns—formal or informal—shape what buyers see.

CRMLS operates one of the largest private databases of home listings in the country, essential to Zillow's business model. That context matters when trying to understand why a California-specific concern might trigger a nationwide response.

For buyers: same property, different platforms, different access to the same underlying information. On Zillow, you get a hyperlink. On Redfin, Realtor.com, and Homes.com, you get climate risk scores directly on the listing. Whether you see the information depends on which platform you use and what pressure that platform is responding to.

Building the plugin meant figuring out how to access what was already public. Matouka's code queries official government APIs—CAL FIRE for wildfire hazard zones, FEMA for flood data, Cal-Adapt for climate projections. Six risk indicators total.

The technical sophistication required to restore this information versus the simplicity of what it displays—risk indicators below the property price—that gap between information availability and information accessibility is the whole story.

Searching for Risk in a Fragmented System

If you want climate risk data for a property you're considering, you have options:

• First Street's website offers free property-level assessments for any U.S. address
• FEMA flood maps are publicly available
• Cal-Adapt provides California-specific projections
• Or install Matouka's plugin, if you're searching California properties on Zillow and you happen to know it exists

This requires knowing these resources exist and having the time to use them.

There's no federal requirement for home sellers to disclose flood risk or previous flood damage. Twenty-one states have no flood disclosure requirements at all. The information exists—in government databases, in private risk models, in historical records. But the system for getting it to buyers before they make irreversible financial decisions remains voluntary, fragmented, and subject to industry pressure.

Searching for flood risk data and finding nothing where it used to be feels like someone made a decision about what information you should have, and that decision wasn't made with your interests in mind.

The Market Reality Nobody Disputes

Disclosing flood risk decreases home sale prices. First Street CEO Matthew Eby noted that pressure to remove climate data "didn't arise when housing markets were roaring and inventory was plentiful. It's happening now, during one of the toughest real-estate environments in decades."

Climate risk information affects market behavior. That's not disputed. Whether buyers should have easy access to it before they make offers—that's what's being fought over.

When Prediction Becomes Inconvenient

First Street's models aren't perfect—no climate risk prediction is. But when First Street defended its wildfire modeling by noting it identified more than 90% of homes that burned in January 2026's Los Angeles Eaton Fire as being at severe or extreme risk (while California's own maps put just 21% in the highest hazard zone), it highlighted a different tension.

Models that predict future risk will always flag properties that haven't yet experienced damage. That's what prediction means. The timing of the removal—November 2025, as housing markets struggled and climate risk became harder to dismiss—suggests something beyond accuracy concerns drove the response.

What the Workaround Reveals

Matouka's plugin is still in beta testing. He's welcoming feedback as he evaluates readiness for wider use. But someone felt compelled to build a technical workaround to restore publicly available information that a major platform removed. That tells its own story about whose interests the current system serves.

More than 80% of buyers now consider climate risks when purchasing a home, according to Zillow surveys. But the infrastructure for accessing that information remains contested territory. Platforms can add it, then remove it. MLS systems can question it without changing rules. Buyers can search for it across multiple disconnected sources, or install plugins built by individual experts, or rely on whatever their agent happens to know.

In November 2025, climate data became harder to access on the platform where most buyers start their search. The timing coincided with a stressed housing market where risk information had measurable effects on sales and prices. The accuracy questions were real, but so was the market pressure.

The disclosure battle is unfolding now, with no clear resolution. Will other platforms follow Zillow's lead? Will regulators intervene? Understanding how the system actually works—how information flows through private databases, how platform decisions respond to industry pressure, how individual actors create workarounds when official channels close—matters when you're evaluating what you're not being shown while searching for a home.

Someone had to build a browser extension to see publicly available data about the largest financial decision most people make. That's where we are.