Exoclimes_Conference_booklet1

TALKS/POSTERS ABSTRACTS *
INSIGHTS FROM SOLAR SYSTEM PLANETS
Gloomy planets: overcoming remote sensing challenges for cloudy atmospheres
Joanna K. Barstow — University of Oxford
For most known planets, our only knowledge about their atmospheres comes from remote
sensing and spectroscopic analysis. There are often multiple, degenerate atmospheric
states that could produce the observed spectra, and usually more complex atmospheric
models result in greater numbers of permitted atmospheric states. The inclusion of clouds
in an atmospheric model increases its complexity. The size of the cloud parameter space,
the nature of the condensate, size of condensate particles, number density and location
within the atmosphere all influence spectral features.
Recent analyses of the best-studied extrasolar planets, such as HD 189733b and GJ
1214b, indicate that clouds are as ubiquitous outside the solar system as they are inside it.
Their probable presence on these planets can no longer be ignored, but the quality and
spectral coverage of remote sensing data for exoplanets and the outer planets in our own
solar system limits our ability to draw conclusions about their nature. We are left with a
vast, underconstrained model parameter space to explore. In addition, the presence of
uncharacterised clouds in planetary atmospheres can prevent us from placing constraints
on temperature structure and chemistry due to model degeneracy, or can result in
mistaken conclusions based on incorrect assumptions.
I explore the significance of different cloud properties for reflection, emission and
transmission spectra of planetary atmospheres, including examples such as the extremely
detailed characterisation of the H2SO4 cloud on Venus, the hints of enstatite clouds on HD
189733b, and the possibility of Titan-like hydrocarbon hazes on GJ 1214b. I will present
suggestions for a framework to explore cloudy solutions for data-poor planets.
The structure of the Intertropical Convergence Zone over a wide range of
atmospheric circulations simulated with an idealized GCM!
Sean Faulk — UCLA!
One of the most prominent features of the Earth's large-scale circulation in low latitudes is
the intertropical convergence zone (ITCZ), where tropical precipitation is concentrated in a
relatively narrow latitudinal band. Given that small changes in the ITCZ can result in large
local changes in precipitation, factors that control its structure and position have been
widely investigated in the literature. In other planetary settings such as Mars and Titan, it
has been argued that an ITCZ can migrate significantly off the equator into the summer
hemisphere, perhaps even to the summer pole. The dynamical, thermodynamical and
radiative mechanisms controlling seasonal ITCZ migrations has only begun to be explored.
Exploration of the ITCZ behavior in a wide parameter space is important to understand the
fundamental dynamics of the Earth's ITCZ and also to characterize climates on other
planets. Here, we examine the structure of the ITCZ over a wide range of atmospheric
* Arranged by topic in six categories. See the list of participants (p.10) to find page of specific abstract
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