Mayor Karen Bass Appoints New Chief Heat Officer

On March 16, Mayor Karen Bass addressed the public at the Pecan Recreation Center concerning an impending heat wave. This announcement comes after Bass’s administration discreetly replaced Marta Segura with Daniela Simunovic as the chief heat officer on May 31. Simunovic previously served as the senior director of climate and sustainability under Bass for three years.

The chief heat officer role involves managing the city’s strategy against extreme heat, regarded as a significant climate threat in California. Simunovic also leads the Climate Emergency Mobilization Office, a position previously held by Segura. This change in leadership follows Bass’s earlier proposal to eliminate the office due to budget constraints, which was rejected by the L.A. City Council. Consequently, the office was relocated from Public Works to the Emergency Management Department.

Los Angeles established the Climate Emergency Mobilization Office in early 2021 to direct city efforts to minimize greenhouse gas emissions and safeguard residents from climate-related disasters. The office’s director was designated as the city’s chief heat officer, making Los Angeles the third city in the U.S. to formalize this position, following Phoenix and Miami.

Heat-related illnesses are prevalent during peak temperatures, often representing nearly 1% of emergency department visits in L.A. County. In 2025, there were 10 recorded deaths attributed to heat, according to a recent dashboard.

In 2025, Segura’s salary was documented at approximately $222,000, whereas Simunovic earned about $161,000 in her previous role. Before joining L.A. City’s administration, Simunovic was a senior advisor at the California Air Resources Board, focusing on air pollution control.

Simunovic’s appointment was first reported by Climate Colored Goggles, a Substack publication. The mayor’s office confirmed the appointment in a statement, citing broad support from stakeholders and city partners. They highlighted Simunovic’s leadership during the current Extreme Heat Warning affecting Los Angeles.

The Climate Emergency Mobilization Office continues to collaborate with community partners in developing the City’s Heat Action and Resilience Plan, expected to be completed by early 2027. Despite earlier proposals to cut the office, Mayor Bass has reiterated several climate objectives for Los Angeles, including the transition to 100% renewable energy by 2035.

Bass’s Climate Action Plan, released in April, aims to double solar power capacity locally by 2030 and reduce fossil fuel usage in both public buildings and transit systems. The plan also proposes initiatives to mitigate heat risks by increasing tree planting for shade, creating cooling centers for relief during high-temperature periods, and finalizing the Heat Action and Resilience Plan.