Seminar by Ana Lobo, UC Irvine
In the race to detect life beyond the Solar System, rocky M-dwarf planets are increasingly observable and offer exciting prospects. Climate studies of these planets often assume an ocean-covered world. However, M-dwarf habitable zone planets may struggle to acquire and retain water throughout their lifetimes, suffering from enhanced heating and high-energy radiation during early stellar evolution, and persistent stellar flares, such that water-limited land planets may be especially common. Land planets can have uniquely diverse climates, with large temperature gradients. Our recent work shows that, unlike aquaplanets, they can be in a “terminator habitability” climate regime. With scorching dayside and freezing nightside temperatures, their habitable surface areas are confined to the terminator. Meanwhile, comparable aquaplanets lose water to nightside cold-trapping or water vapor escape, limiting water availability over time. In this talk I will show how these results, combined with observational advantages for arid planets, indicate land-planets will be attractive candidates for early detections of habitability.
Host: David Kipping