Former USC undergraduate Adam Vaccaro (now at NASA/JPL) completed and published an application of GraphEM (developed by former USC postdoc Dominique Guillot) to surface temperature datasets. See his 2021 Journal of Climate paper here. Graph theory can be used to fill in gaps in climate data, and to analyze teleconnection patterns!
Former USC graduate student Feng Zhu published his third thesis chapter on the controversial influence of volcanic eruptions on the El Niño-Southern Oscillation phenomenon. See his 2022 Nature Communications paper here, outlining the many reasons why establishing a consistent relationship using paleoclimate data is so difficult.