Titan’s atmospheric circulation and hydrologic cycle

We are working to better understand the climate and hydrologic cycle of Saturn’s moon Titan, a unique yet Earth-like world with an exotic but recognizable hydrologic cycle based on methane. Titan is the only body in the Solar System besides Earth with a massive nitrogen atmosphere and stable surface liquids, and its climate system plays an important role in many observable phenomena. In addition to having an atmosphere full of organic molecules, Titan likely hosts a sub-surface water ocean; it is therefore a key target for astrobiological exploration.

Our main tool to investigate Titan is our ever-evolving climate model, the Titan Atmospheric Model, a general circulation model that is now coupled to a self-consistent surface hydrology model. We supplement our simulations with theory and analysis of observations of Titan, a wealth of which is available from the Cassini mission.

Take a look also at the Dragonfly portion of our Collaborations page!

Some relevant papers:

  • Lora et al. (2022): This paper investigates the influences of topography and orbital forcing on the methane cycle
  • Faulk et al. (2020): This paper describes the coupling between atmosphere and surface hydrology that enables a self-consistent simulation of Titan’s climate
  • Lora et al. (2019): This paper compares three Titan climate models in preparation for the Dragonfly mission
  • Mitchell & Lora (2016): A review paper about Titan’s climate
  • Lora et al. (2015): This paper describes the original version of our Titan Atmospheric Model (TAM)

Earth’s evolving hydrologic cycle

Another area of interest in our group is Earth’s water cycle, and how it has changed in response to various drivers over the past several million years, with a particular focus on atmospheric rivers. Atmospheric rivers are synoptic features of the extratropical atmosphere that are responsible for a majority of poleward vapor transport, and they deliver water to all continents, sometimes in extreme precipitation events.

How do natural and anthropogenic climate drivers affect the mid-latitude water cycle? And how has it evolved in the past in response to changes in, for example, ice sheets? These are questions we address in our group, with a combination of global climate models, observations, and climate reconstructions. 

Take a look also at the ARTMIP portion of our Collaborations page!

Some relevant papers:

  • Baek & Lora (2021): This paper explores the influences of anthropogenic aerosols and greenhouse gases on atmospheric river intensity
  • Skinner et al. (2020): This paper discusses atmospheric rivers and the hydrologic cycle during the early and mid Holocene, and describes our tracking algorithm
  • Lora & Ibarra (2019): This paper examines our understanding of the changing hydrologic cycle of North America since the last ice age
  • Lora (2018): This paper investigates the hydrologic cycle of North America at the last ice age
  • Lora et al. (2017): This paper explores the impact that glacial conditions had on North Pacific atmosheric river behavior

Other areas of interest

We also investigate various other topics, including the atmospheres and climates of other planets (and exoplanets), climate variability, and the connections between the atmosphere and surface (through the boundary layer). We are interested in a broad, mechanistic understanding of climate, and bridging terrestrial climate and planetary sciences.

Some relevant papers:

  • Baek et al. (2023): This paper describes the connection between atmospheric river variability and annular modes
  • Battalio & Lora (2021): This paper documents the presence of annular modes of variability on Mars and Titan

Take a look at our Publications and Collaborations pages for more information!