Over the past couple of years, my research interests have evolved and expanded. While I maintain interest in understanding the dynamics of tropical cyclones and techniques that can be used to improve forecasts, most of my recent research is more broadly focused in tropical meteorology. Deep thunderstorm (or convective) activity occurs often in the tropical environment, and clouds that extend to the top of the troposphere spread out laterally and form anvil clouds that are composed largely of ice particles. These anvil clouds survive for longer than the parent thunderstorm and can have measurable effects on radiative transfer in the troposphere. In mesoscale convective systems (MCSs), the deep thunderstorm activity often develops into a cohesive squall line, which is then trailed by a large area of lighter precipitation and a broad shield of ice anvil clouds that trails the whole system. Part of my research has been to quantify the effects of these anvils on radiative heating in the atmosphere using data from cloud radars run by the US Department of Energy. We can then compare the heating generated by anvil
clouds to latent heating produced by the precipitating areas of an MCS. We may also compare the structure of anvil clouds and precipitating areas in a high-resolution mesoscale model to those that we have observed. A correct model of the anvil can provide us some additional physical insight into how it is formed and maintained. By repeating this process for several different areas of the tropics, we learn of the differences between anvil structures over continents and over oceans.
In September 2011, as part of a large field campaign, I traveled to the Maldives, which are located south of India in the central equatorial Indian Ocean. Specifically, I was among many of the personnel located at the radar "supersite" on Addu Atoll
. The project, known as CINDY2011/DYNAMO/AMIE
(different titles by different agencies), aimed to gather in-situ atmospheric and oceanic observations over the central Indian Ocean and surrounding domain between October 2011 and February 2012. Using the wealth of data collected, we aim to examine the relative roles of large-scale tropical dynamics and the cloud population to moistening of the troposphere prior to the onset of a Madden-Julian Oscillation
(MJO). The MJO has important impacts on weather, such as tropical cyclone activity, as it propagates westward around the globe from its origin in the Indian Ocean. However, due to our current limited understanding of the initiation process, our computer models do not properly simulate the MJO. Many questions remain as we begin digging into the dataset. Why does an MJO initiate at some times and not at others, when conditions, at first glance, appear the same? How important are cloud moistening processes, such as evaporation or sublimation of anvil clouds, in MJO initiation? How variable is the humidity on temporal and spatial scales over the tropical ocean? Can this variability be reliably observed in situ by a radar system?