The 2022 Robert Hofstadter Memorial Lectures
Announcing the 2022 Robert Hofstadter Memorial Lectures
The Physics Department is excited to announce that the 2022 Robert Hofstadter Memorial lecture will be given by Dr. William D. Collins. Dr. Collins is an internationally recognized expert in climate modeling and climate change science. His personal research concerns the interactions among greenhouse gases and aerosols, the coupled climate system, and global environmental change.
Dr. Collins is a Fellow of the American Association for the Advancement of Science (AAAS), the American Physical Society (APS), and the American Geophysical Union (AGU). He was awarded the AGU’s Tyndall History of Global Environmental Change Lectureship in 2019. He was a Lead Author on the Fourth Assessment of the Intergovernmental Panel on Climate Change (IPCC), for which the IPCC was awarded the 2007 Nobel Peace Prize, and served as a Lead Author on the Fifth and recent Sixth Assessments. His role as Chief Scientist in launching the Department of Energy’s Accelerated Climate Model for Energy (ACME) program was awarded the U.S. Department of Energy Secretary’s Achievement Award on May 7, 2015. Before joining Berkeley and Berkeley Lab, Dr. Collins was a senior scientist at the National Center for Atmospheric Research (NCAR) and served as Chair of the Scientific Steering Committee for the DOE/NSF Community Climate System Model project.
Dr. Collins received his undergraduate degree in physics from Princeton University and earned an M.S. and Ph.D. in astronomy and astrophysics from the University of Chicago. Dr. Collins’ public Hofstadter lecture on Monday, April 11, 2022 is followed by the Applied Physics/Physics colloquium on Tuesday, April 12, 2022. Please join us for these fascinating lectures.
Dr. William D. Collins
Director, Climate and Ecological Sciences Division, Lawrence Berkeley National Laboratory
Professor in Residence, Department of Earth and Planetary Science, University of California, Berkeley
Public Lecture (7:30 PM on Monday, April 11, 2022)
Hewlett Teaching Center, room 200 (in-person attendance limited to Stanford affiliates)
Zoom link
Passcode: 595377
“Glimmers of Hope: Paths Forward on Climate Change”
As we approach the 52nd celebration of Earth Day on April 22nd, it is an opportune time to take stock of our collective progress towards addressing human-induced global warming. Fortunately we understand better than ever the causes and consequences of recent climate change, and we are amid a world-wide dawn of renewable energy. In this talk, we summarize the most recent assessments of our global environment from the Intergovernmental Panel on Climate Change. These assessments provide strong evidence and ample justification for accelerating a comprehensive transition to carbon-neutral or carbon-free power. Due to delays in starting this transition, the world may also need to weigh more drastic measures to avoid dangerous levels of global warming. The measures include geoengineering to cool the planet as well as carbon dioxide removal from the atmosphere and oceans. We discuss some of the major upsides and downsides to these contingency plans, and we conclude with basic research underway at Berkeley Lab on new methods to remove carbon dioxide from the climate system.
Afternoon Colloquium (3:30 PM on Tuesday, April 12, 2022)
Hewlett Teaching Center, Room 200 (in-person attendance limited to Stanford affiliates)
Zoom link
Passcode: 191647
“Prospects for estimating Transient Climate Response to Greenhouse Gases using the Fluctuation Dissipation Theorem”
One of the core metrics for climate change is the steady-state increase in global surface air temperature with doubled concentrations of CO2 known as the Equilibrium Climate Sensitivity (ECS). Best estimates of ECS remain uncertain to factors of O(3) despite intensive research since the first comprehensive assessment of global warming due to CO2 over forty years ago (Charney et al., NAP, 1979). The large range in ECS propagates into projections of the future physical state of the climate system, and it introduces considerable incertitude into policy responses designed to mitigate global warming. The uncertainty in ECS stems largely from multiscale and multiphysics feedbacks introduced by components of the climate system, especially by clouds and the cryosphere, for which we lack first-principles theories.
In this talk, we discuss the prospects for estimating a related metric, the Transient Climate Response (TCR), using the Fluctuation Dissipation Theorem (FDT). TCR is the global mean temperature change under a hypothetical 1%/year increase of CO2 at the time when atmospheric CO2 concentrations have doubled. TCR and ECS are closely related through the First Law of Thermodynamics. Following concepts first advanced by Goody et al (1998), we explore whether TCR could be reliably estimated by applying the FDT to satellite observations of the Earth’s spectral radiation. The forcing, response, and feedbacks of the climate system can be readily detected and attributed in these spectra, and equator-to-pole gradients in the spectra govern the primary energy transports in the climate system. This estimation process can be tested and validated using a multi-model ensemble of climate simulations recently assessed by the Intergovernmental Panel on Climate Change. Recent theoretical developments have eliminated questionable assumptions that have compromised prior attempts to apply FDT to climate. We show how these developments will reduce uncertainties in the estimation process and discuss the impact of this reduction on climate science going forward