[2] Cobb completed her PhD in oceanography at Scripps in 2002, hunting El Niño events in a sediment core from Santa Barbara.

She and her team collected ancient coral fragments from the islands of Kiribati and Palmyra, aged them with uranium–thorium dating and then used the oxygen isotope ratio cycle to measure the intensity of El Niño events over the last 7,000 years.

[5] Cobb is on the editorial board of Geophysical Review Letters[6] and acted as lead author on the Sixth Assessment Report of the Intergovernmental Panel on Climate Change.

[15] Cobb is an advocate for outreach with communities, and regularly lectures to schools, colleges and other public groups, on climate science.

[17][18] In February 2019, Cobb testified before the House Committee on Natural Resources for the hearing, "Climate Change: Impacts and the Need to Act.

"[19] In this testimony, she described how the 2016 Pacific Ocean El Niño wiped out 90 percent of the corals in her study site, saying, "I had a front-row seat to the carnage."