In the hills of Emilia-Romagna, a bank vault holds more than half a million wheels of Parmigiano Reggiano, worth well over 300 million euros.

The vault belongs to the bank Credito Emiliano, known colloquially as Credem, which has long accepted young wheels of Parmigiano Reggiano as collateral for loans to local dairy farms since 1953.

But now, extreme heat is threatening Italy’s “cheese banks,” and economists who study heat’s effect on growth say the exposure runs well beyond a single vault but into the country’s vineyards, its olive groves, and its broader economy.

A blockchain-backed cheese loan collateral program

After receiving the wheels of cheese from dairy farmers, a Credem subsidiary, Magazzini Generali delle Tagliate, ages the wheels in two warehouses in Reggio Emilia and Modena. Producers typically receive 60% to 80% of a wheel’s value upfront.