Here are options for a Physics Grad student like you, you might like these:
Intermediate Level:
"Dire Predictions: Understanding Climate Change" by Michael E. Mann and Lee R. Kump
This book offers a more in-depth exploration of climate science, including discussions on climate modeling, historical climate data, and predictions for the future.
"The Sixth Extinction: An Unnatural History" by Elizabeth Kolbert
While not exclusively focused on climate science, this Pulitzer Prize-winning book delves into the interconnectedness of species extinction and climate change, providing a deeper understanding of their effects.
Advanced Level:
"The Physics of Climate Change" by Lawrence M. Krauss
This book delves into the physics behind climate change, explaining the scientific principles that underpin the climate system. It's recommended for readers with a strong background in physics and science.
"Climate Change Science: A Modern Synthesis" edited by G. Thomas Farmer and John Cook
This comprehensive book provides an overview of climate science from various perspectives, making it suitable for those looking for an in-depth exploration of the subject.
Remember that climate science is a multidisciplinary field, and books on the topic often touch on aspects of physics, chemistry, biology, and more. Choose a book that matches your current knowledge level and interests, and don't hesitate to further explore specific areas that intrigue you.