Professor Discusses Future of Extreme Weather Research

 

Professor Sharan Majumdar

Professor Sharan Majumdar

Professor of Atmospheric Sciences Sharan Majumdar recently penned an article on the future of research aimed at improving predictions of and responses to high-impact weather events. Published in the March issue of the Bulletin of the American Meteorological Society, the flagship journal of the American Meteorology Society, Majumdar and colleagues discuss the post-THORPEX (The Observing System Research and Predictability Experiment) scientific research planning efforts.

Radar image of Tropical Cyclone Isaac

Radar image of Tropical Cyclone Isaac

THORPEX, a 10-year research and development program organized under the World Meteorological Organization (WMO)/World Weather Research Programme (WWRP), was designed to accelerate improvements in the accuracy and use of 1-day to 2-week numerical weather predictions and concluded in 2014.

“We are planning out the next decade(s) of national and international research with big ideas and broad goals,” said Sharan Majumdar, who was put in charge of steering the initiative. “One important element is to define our national goals, such as improving responses to flash floods, or multi-hazard problems in big cities like New York.”

According to the authors, the “proposed new U.S. high-impact weather research initiative promises significant benefits for the nation in terms of research advances that will directly benefit the entire weather enterprise in reducing loss of life and property.” Read more

 

Faculty, Student and Alumni Updates

Professor Amy Clement Named 2015 AMS Fellow

Amy Clement 1UM Rosenstiel School Professor Amy Clement has been elected a 2015 Fellow of the American Meteorological Society (AMS), the nation’s leading professional society for scientists in the atmospheric and related sciences. The award was presented at a special reception on Jan. 4 2015 at the AMS annual meeting in Phoenix, Arizona.

Clement, an associate dean and professor of atmospheric sciences, leads a climate modeling research group at the UM Rosenstiel School, which aims to better understand various aspects of Earth’s climate, from Saharan dust and clouds to El Niño/Southern Oscillation (ENSO), which is the largest mode of variability in the modern climate. Clement’s research focus is on fundamental aspects of the climate system, including understanding why the climate changed in the past, and predicting how it will change in the future.

Grad Student Gives Keynote at Sailing Symposium

waterlust-nsps-2 (1)Rosenstiel School Ph.D. student Patrick Rynne recently gave a keynote lecture at the National Sailing Programs Symposium in New Orleans. His talk focused on the inherent connection between sailing and the ocean and how decisions we make impact that relationship and how his cause-based organization, Waterlust, came to be and what small (or big) steps that organizations can take to help promote environmental awareness.

Patrick founded Waterlust, a student-run project aimed at inspiring the world to consider their relationship with water through online film and photography, while a student at RSMAS.

Alumna Joins MPS Program, Awarded Suncoast Emmy®

JulieHUM Rosenstiel School alumna Julie Hollenbeck recently joined the Master of Professional Science (MPS) Program team as associate director. Julie has extensive experience within and among the University of Miami community and has worked in TV broadcast journalism, communications, project management, and outreach and education.

Julie was honored in December 2014 with a Suncoast Emmy® for her work on Living Fossils, an episode from WPBT2’s original television series Changing Seas. Hollenbeck worked as an associate producer for Changing Seas.

The episode, Living Fossils, produced by Changing Seas series producer Alexa Elliott, features research on deep-sea crinoids, a flower-like animal related to starfish, urchins and other echinoderms. Crinoids can be traced back to the Paleozoic era yet very little is known about this enigmatic creature. Researchers featured in the episode explored the depths from a deep-sea submarine, filling in previously unknown details on the lives of crinoids.

Julie is also a Ph.D. candidate in the University of Exeter’s European Center for Environmental and Human Health program.

The MPO Best Paper Award Goes To…

UM Rosenstiel School Ph.D. student Katinka Bellomo received the Best Paper Award from the Division of Meteorology and Physical Oceanography (MPO) for her research paper recently published in the American Meteorology Society’s Journal of Climate.

“Receiving the MPO best paper award is a huge personal satisfaction,” said Katinka. “This is the first paper of my dissertation and of my life.”

Addu Atoll lagoon at sunset

The paper, titled “Observational and Model Estimates of Cloud Amount Feedback over the Indian and Pacific Oceans,” addressed the largest uncertainty in climate models – cloud feedback – by examining observations of cloud cover taken from ships and satellites from 1954 to 2005. The results of this paper represent the first observational long-term estimate of cloud feedback.

In response to greenhouse gas forcing, the Earth would naturally cool off by emitting more radiation back into space. However, feedback mechanisms, from clouds, can increase or reduce this cooling rate.

“I am satisfied that the paper shows how to handle the uncertainties in observations and provides a methodology to estimate cloud feedbacks from these observations,” said Katinka.

Congrats Katinka!

What Caused the Rapid Intensification of Super Typhoon Haiyan?

Typhoon Haiyan at peak intensity on November 7, 2013. Credit: NASA

Typhoon Haiyan at peak intensity on November 7, 2013. Credit: NASA

During the AMS Hurricane and Tropical Meteorology meeting in San Diego last week, Rosenstiel School professor Nick Shay presented research on the role ocean warming played in the rapid intensification of last year’s devastating Super Typhoon Haiyan in Southeast Asia.

Shay’s study suggests that temperature fluctuations from semi-diurnal internal tides need to be analyzed to fully understand the causes of rapid intensification as the storm went over the warm pool of water in the western Pacific prior to landfall in the Philippines.

Using temperature, salinity and current data collected as Haiyan made a direct hit over the Japan’s Triton buoy (formerly a NOAA TAO buoy), along with satellite-derived data from the SPORTS climatology model (Systematically merged Pacific Ocean Temperature and Salinity developed by Rosenstiel School graduate student Claire McCaskill), Shay’s research team examined ocean warming conditions prior to Haiyan at the thermocline, a distinct ocean temperature layer that is known to fluctuate seasonally due to tides and currents.

 

infrared satellite loop of Typhoon Haiyan in the Philippines. Credit: NOAA

infrared satellite loop of Typhoon Haiyan in the Philippines. Credit: NOAA

Internal tides are known to create large temperature fluctuations. Shay suggests that the upper ocean heat content was important in the rapid intensification of Haiyan similar to what is observed in the Atlantic Ocean basin. While the semidiurnal tides were amplified in the warming thermocline in this regime, they have to be removed from the data to accurately evaluate questions related to the roles climate change and oceanic warming played in the storm’s intensification.

At the Heart of a Hurricane Forecast

One of the many challenges in hurricane forecasting is incorporating observational data into forecast models. Data assimilation, as scientists refer to it, is the process of combining observational data – information obtained by satellites, radars or from instruments deployed into storms by aircraft – into a numerical weather prediction model.

Incorporating real-world temperature, wind, moisture or atmospheric pressure from multiple sources is a core component of hurricane science and vital to provide improved forecasts of both the track and intensity of storms. How to incorporate new types of observational information into a model is at the very heart of hurricane forecasting.

At the American Meteorology Society’s 31st annual Hurricane and Tropical Meteorology meeting in San Diego this week, Rosenstiel School Professor Sharan Majumdar discussed new approaches to improve data assimilation.

Typhoon Sinlaku (2008), as seen from Terra Satellite on September 10 2008. Credit: NASA

Typhoon Sinlaku (2008), as seen from Terra Satellite on September 10 2008. Credit: NASA

Citing the Ph.D. research of Rosenstiel School graduate student Ting-Chi Wu, Majumdar discussed the assimilation of temperature and moisture data obtained from satellite-based advanced Infrared (IR) soundings measured by polar-orbiting satellites of Typhoon Sinlaku during the 2008 Pacific typhoon season. Wu’s studied the period of storm intensification as Sinlaku intensified into a category-2 typhoon. Her conclusion was that the assimilation of temperature and moisture show promise in improving forecasts of hurricane and typhoon intensity, though more work needs to be done to improve their use.

Majumdar also provided an overview of strategies to assimilate observations to improve numerical weather forecasts of the track and structure of storms. He showed that targeted aircraft observations in select areas and satellite observations from both within and outside a tropical cyclone are beneficial.

Hurricane Intensity Study Wins ‘Outstanding Poster’ Award

UM Rosenstiel School Meteorology and Physical Oceanography graduate student Falko Judt was awarded first prize in the Outstanding Student Poster competition at the American Meteorology Society’s 94th Annual Meeting in Atlanta, Georgia. Falko shares the research behind his poster, titled “Tropical Cyclone Intensity Forecasting: Predictability and Uncertainty.”

MPO Graduate Student Falko Judt

MPO Graduate Student Falko Judt

“The main goal of my research is to better understand and therefore better predict the intensity of hurricanes. Computer model forecasts are getting better with forecasting where a hurricane will go (its track), but we’re still having a hard time telling in advance how strong a storm might become (intensity).

One school of thought is that it is very difficult to accurately forecast intensity for more than 2 days because small-scale and not well understood processes in the inner regions of a storm. In the inner core, energy from the ocean surface is converted to strong winds in thunderstorm clouds that surround the eye, forming the hurricane rain bands. Knowing the exact arrangements and processes going on in these clouds is, according to this hypothesis, very important for forecasting changes in a hurricane’s intensity.

On the other hand, some scientist argue that these small-scale processes going on within the hurricane don’t matter too much, and the really important factors determining the strength of a storm are properties of the large-scale environment surrounding it. For example, high ocean temperatures, high atmospheric humidity values and low wind shear are known to lead to intensification of hurricanes.

My research was testing these hypotheses by adding stochastic (random) perturbations to state-of-the-art computer models (ensemble forecasts) predicting the intensity of Hurricane Earl of 2010, which is a storm that already happened, so we can compare the forecasts to what was observed.

In one ensemble, tiny perturbations with the size of clouds were added to the model, and another ensemble had larger perturbations on the scale of real weather systems — about a few hundred to thousands of miles. We found that very small perturbations do not change the properties of the hurricane predictions, and even larger-scale perturbations only cause some fluctuations in their forecasted intensity.

We therefore concluded that ultimately the environmental conditions determine how strong a storm will be. This is good news because we have better knowledge about and data from a hurricane’s environment.

Based on this research presented in my poster, we might even be able to tell how strong a storm will become 7 day in advance with the help of improving computer models and better observations from the surrounding atmosphere. The predictability limit seems to be longer than what had been expected.”

— Falko Judt