Peter Kalmus (born May 9, 1974) is an American scientist and writer based in Altadena, California. He is a data scientist at NASA's Jet Propulsion Laboratory as an associate project scientist at UCLA's Joint Institute for Regional Earth System Science & Engineering.
In addition to his scientific work, he is the author of the book, Being the Change: Live Well and Spark a Climate Revolution. A documentary by the same title complements the book. In addition to authoring articles about climate change, he is the founder of the website noflyclimatesci.org and co-founder of the app, Earth Hero: Climate Change.
Education and early career
Kalmus attended Harvard University, where he received his Bachelor of Science in physics in 1997. At Harvard, he used Fourier-transform microwave spectroscopy to discover and categorize the quantum-mechanical rotational spectra of several cyanopolyynes which were subsequently found in interstellar clouds. He then taught high school physics in Massachusetts and wrote software in New York City. In 2004 he enrolled in graduate school at Columbia University and received his PhD in physics in 2008. His PhD work involved searching for gravitational waves as a member of the LIGO Scientific Collaboration (thesis: "Gravitational Waves Associated with Soft Gamma Repeater Flares"). He continued his work with LIGO as a postdoctoral scholar at the California Institute of Technology, leading major full-collaboration searches for gravitational waves from magnetars, gamma ray bursts and supernovae and contributing to the precise calibration of the world's gravitational wave observatories.
Research
After focusing on LIGO related work for several years, Kalmus's focus transitioned into earth and climate science. Kalmus's recent research centers on cloud physics, specifically improving basic understanding of marine stratocumulus clouds and severe convective weather such as tornadoes with the goal of improving projections of how these phenomena will change as the planet heats, using remote sensing data, in situ data, and models. Marine stratocumulus clouds reflect incoming sunlight, cooling the planet, and are difficult to model accurately in climate models; this makes them a major source of uncertainty in climate projections.
A common thread in his research is improving the utility of satellite observations of the Earth. His work on severe weather unlocks the potential of polar orbiting satellites to observe rapidly changing convective environments by using air parcel trajectory modeling to span the temporal gap between satellite overpass and convective initiation. He has used in situ data from a ship-based campaign to bias-correct the CloudSat warm rain retrieval. He also uses in situ data to validate retrievals from the AIRS instrument on the Aqua (satellite).
Recently, Kalmus has begun to work in the nascent field of ecological forecasting. He is the principal investigator on a NASA grant to study the projected future of the world's coral reefs with greater accuracy and higher resolution. Coral reefs are rapidly succumbing to ocean heat waves and ocean acidification.
He has co-authored over 100 peer-reviewed scientific articles in physics and Earth science, with a majority having come from his previous participation in the LIGO Collaboration.
Activism and public engagement
Kalmus is a science communicator whose efforts center on shifting culture away from fossil fuel acceptability. He tweets as @ClimateHuman and as of April 2022 is the most-followed climate scientist on Twitter. He focuses in particular on encouraging the Earth science and other academic communities to speak out with greater urgency on the need for climate action.
He has been featured in many media outlets, including Mother Jones, PRI's The World, CBC Radio, Deutsche Welle, BuzzFeed, The Intercept, and Quartz, and most often speaks to the need for an immediate and massive climate mobilization and how individuals can "vote" for this mobilization through their actions, via both activism and emissions reduction. He frequently speaks to the need for a carbon fee and dividend policy as part of the mobilization, in which fossil fuel becomes increasingly costly as the carbon fee rises every year and 100% of the net revenue is returned equitably to the people, making the policy fiscally progressive.