Award-Winning Faculty! German Cross of Merit and more…

Professor Graber receives the German Cross of Merit

Hans GraberHans C. Graber, UM Rosenstiel School professor of ocean sciences and director of the Center for Southeastern Tropical Remote Sensing (CSTARS), was awarded the Federal Cross of the Order of Merit, or Bundesverdienstkreuz, by the German government, the highest civilian award given by the Federal Republic of Germany. The Consul General Juergen Borsch presented the Federal Cross of Merit to Graber at an event on March 20 in Miami.

The order was established in 1951 to provide awards “for achievements that served the rebuilding of the country in the fields of political, socio-economic and intellectual activity, and is intended to mean an award of all those whose work contributes to the peaceful rise of the Federal Republic of Germany.”

Graber’s research focuses on radar remote sensing of hurricanes and typhoons, understanding air-sea interactions and the generation of ocean waves and storm surge.

Notable recipients of the Bundesverdienstkreuz include, Queen Elizabeth II and her husband Prince Philip, Duke of Edinburgh, Mikhail Gorbachev and Queen Sofía of Spain.

 

Professor Amy Clement Receives Mentor Award

Amy ClementAmy Clement, associate dean and professor of atmospheric sciences is the second recipient of the UM Rosenstiel School Outstanding Mentor Award. Clement was presented the award by the Graduate Academic Committee at a ceremony on May 20 at the School. At the award ceremony she gave a talk titled, “A discussion on mentoring and being mentored.”

The award was designed to recognize an exceptional faculty mentor and based upon the recommendation of a committee of Rosenstiel School students, post-doctorate researchers and faculty.

Clement 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.

Marine Chemistry Pioneer Frank Millero Retires

Dr. Frank MilleroAfter 49 years world-renowned Marine Chemist Frank Millero is retiring as a full professor of ocean sciences from the UM Rosenstiel School. Millero will join the ranks as a professor emeritus while still maintaining his active ocean science research laboratory on campus.

During his academic tenure Millero was instrumental in helping shape current scientific knowledge on the chemistry of seawater, a fundamental component to understand the ocean’s role in global climate change. He has published over 500 works, including one of the premier textbooks on ocean chemistry, and developed the fundamental equation of state of seawater still in use today.

Millero and his research team have traveled the world ocean’s collecting data on carbon dioxide levels at different ocean depths as part of a large, collaborate National Science Foundation-funded project. The 20-year study is helping to understand the environmental effects of the 40 percent of human-generated CO2 that enter the world’s ocean. The next cruise is scheduled for August 2015.

Beyond his scientific accolades, Millero’s devotion to teaching the next generation of scientists and generous philanthropic contributions to the UM Rosenstiel School, athletics, and arts have helped advance the University in many ways.

Millero grew up in Ohio and earned his undergraduate degree at The Ohio State University and a doctorate in chemistry at Carnegie Mellon University in Pittsburgh, where he tended bar for spending money and met his wife, Judith. They have three children: Marta Millero-Quincoses, B.B.A. ’95, a South Florida accountant; Frank III, who teaches at Pratt Institute in New York; and Anthony, who works in merchandising in New York.

We are happy that Frank’s good works and good humor will still be on campus for several more years!

Miami Missions

The University of Miami Rosenstiel School of Marine and Atmospheric Science (RSMAS) is situated on an island just offshore of Miami, linked to the mainland by a causeway. It has exquisite views over the ocean, and its own private beach.

Final_UMAerial_2218

UM Rosenstiel Campus

Surprisingly though, this was not my motivation to visit the school, and I didn’t know how stunning the campus was until I arrived there. Professor Lisa Beal in the Department of Ocean Sciences at the Rosenstiel School was the main attraction, as she is possibly one of the most knowledgeable people on the Agulhas Current, which happens to be the focus of my Ph.D. I am a Professional Development Programme* (PDP) student with SAEON’s Egagasini Node working as part of the ASCA team.  My study is co-supervised by Prof. Beal, who led the Agulhas Current Time-series experiment (ACT, which has now been extended into the ASCA array).

Lisa Beal, Ph.D.

In this ground-breaking study, seven full-depth current meter moorings along with four current pressure inverted echo sounders were placed across the current to follow the trajectory of the descending TOPEX/Jason ground track that leaves the South African coast line at 33.4°S and stretches out to sea approximately perpendicular to the continental slope. The mooring data spans the period 2010-2013, thereby providing 34 months of velocity and transport measurements at an unprecedented resolution.

Valuable dataset

This data is extraordinarily valuable as it can provide insight into the variability of a current which is thought to play a vital role in the meridional overturning circulation, a system of surface and deep currents encompassing all ocean basins. It transports large amounts of water, heat, salt, carbon, nutrients and other substances around the globe, and connects the surface, ocean and atmosphere with the huge reservoir of the deep sea.

IMG_9281 By coupling the mooring data with the overlaid satellite altimetry measurements, Prof. Beal’s team at RSMAS were able to extend the transport data back in time using a proxy, thereby producing 20 years of transport estimates for the Agulhas current from 1993-2013. This dataset will be the foundation of my thesis and was the motivation to work at RSMAS for the very first two months of my Ph.D.

Initially I was apprehensive about spending an extended period of time in Miami as my impression was that the city was all about glitz, glam and superficiality. Never before have I been proven so wrong! The people I met and the places I visited were truly impressive, from the natural beauty of the Everglades and Florida Keys to the mind-blowing creativity of the hipster art district, Wynwood. The impressive sights were complemented by the delicious Cuban food and Latino flair.

A meeting of bright scientific minds

However, my favourite part of the trip was, surprisingly, not the sightseeing and the tasty food, but the Wednesday morning group meetings with Prof. Beal’s research team. This group of extraordinarily bright minds meets once a week to discuss a paper, present their latest research results, or simply brainstorm ideas or challenges for the road ahead.

Being given the opportunity to participate and absorb the ideas flying around the room once a week was an incredible opportunity and education. I have come to realise that being a scientist is not something you can learn by just reading academic journals or processing data, but is better achieved by exercising your curiosity and approaching all scientific statements and findings with a critical mind. “How did they get this result? What processing was undertaken? Why is this different to previous literature? How do we replicate the methodology?” From data analysis techniques, the formation of robust scientific key questions, and the art of finding a signal amidst all the noise, I received a whirlwind education on how to be a scientist.

Research topic

During my time at RSMAS I came up with a very exciting topic for my Ph.D. – how local and remote winds affect Agulhas Current Transport variability.

Figure 1 shows the mean wind speeds for the Indian Ocean from 1993 to 2015 and the position of the ACT /ASCA mooring array. As can be seen from the image, there are two patches of very high wind speeds, one centred around 15S known as the Trade winds, and another south of 50S called the Westerlies. These two maximums in wind speed, and thus wind stress, create a positive wind stress curl between them which, in turn, creates a net northward transport across the basin. This is known as the Sverdrup transport as it is the ocean current pattern produced by the wind induced (Ekman) movement of water.

This northward transport must be balanced by a flow out of the basin – a task that is largely undertaken by the Agulhas Current. The Agulhas is the western boundary flow of the South Indian subtropical gyre and dominates what may be the highest meridional heat flux in the world’s oceans. The leakage of waters from the Agulhas into the South Atlantic is a critical link in the global thermohaline circulation, feeding warm and salty waters into the upper limb of the global overturning circulation, and therefore playing a vital role in the climate system.

Mean winds zone

Figure 1: Mean wind speed (m/s) from 1993-2015 over the Indian Ocean with vectors showing direction overlaid. The position of the ACT/ASCA mooring array off the east coast of South Africa is shown in black.

Regionally, the Agulhas Current exerts a strong control on rainfall and climate over South Africa, acting as a major source of latent heat for onshore wind systems. Furthermore, the current is also of fishing (and thus economic) importance to South Africa, as upwelling and high levels of productivity are induced when it separates from the shelf during a periodic meander event.

Wind-driven dynamics have been shown to have a critical influence on the variability of western boundary currents elsewhere, but this relationship has yet to be addressed in the Agulhas Current. Decadal trends of surface wind stress have indicated an increase in both the Trade and Westerly winds over the Indian Ocean basin.

A variation in the winds across the Indian Ocean basin would result in a modification in the flow of the Agulhas. An alteration in strength of the Agulhas would have a variety of implications, ranging from local effects on the climate of the east coast of South Africa, an adjustment of upwelling affecting fisheries, and on a global scale, an alteration of the volume flux of warm salty water from the Indian to the Atlantic Ocean.

My Ph.D. will endeavour to gain insight into this and shed some light into what has been happening with winds and western boundary current responses in the Indian Ocean over the past 20 years. My two-month trip in Miami was the perfect kick start to my Ph.D. I return home to Cape Town with a topic that I am very passionate about and a strong drive to understand and learn more. Even though it was a reasonably short period of time, it was jam-packed with experiences and lessons.

* The Professional Development Programme of the Department of Science and Technology and the National Research Foundation aims to accelerate the development of scientists and research professionals in key research areas.

–By Katherine Hutchinson, Ph.D. Student, SAEON Egagasini Node

Water, Water, Everywhere: Sea Level Rise in Miami

Like many low-lying coastal cities around the world, Miami is threatened by rising seas.  Whether the majority of the cause is anthropogenic or natural, the end result is indisputable: sea level is rising.  It is not a political issue, nor does it matter if someone believes in it or not.

Tidal flooding on the corner of Dade Blvd and Purdy Ave in Miami Beach in 2010. (Steve Rothaus, Miami Herald)

The mean sea level has risen noticeably in the Miami and Miami Beach areas just in the past decade.  Flooding events are getting more frequent, and some areas flood during particularly high tides now; no rain or storm surge necessary [1].

Diving Into Data

Measurements of sea level have been taken at the University of Miami’s Rosenstiel School on Virginia Key since 1994, with certified daily measurements available online since 1996 (Virginia Key is a small island just south of Miami Beach and east of downtown Miami) [2].  Simple linear trends drawn through annual averages of all high tides, low tides, and the mean sea level are shown below, and all three lines are about 5.2 inches (13 cm) higher in 2016 than they were in 1994.

Annual averages of high tide, low tide, and mean sea level, with linear trend lines drawn through them. The trend line slopes for each time series are labeled. [This chart was updated in Jan 2017 to include verified data through the end of 2016.]

For the following chart, the daily high water mark (highest of the two high tides each day) for 21 years is plotted.  The water levels at high tides are the most relevant because that is when flooding events are more prone to occur.  For reference, the average seasonal cycle is shown by the thin black line, the daily high tide values are plotted with a thin light blue line, and the thick blue line is simply a smoothed version of the thin blue line.  The “lunar nodal cycle” shown by the thin red line also impacts sea level and peaks every 18.6 years (it just peaked in 2016).  The highest water marks in the dataset are annotated… they have historically been associated with the passage of hurricanes, until September 2015 and October 2016 when very high water levels were reached without a storm nearby.

[This chart was updated in Jan 2017 to include verified data through the end of 2016.]

The seasonal cycle has a total amplitude of approximately 10 inches (25 cm) and is highest during September through November.  It was calculated using a 31-day running mean of all 21 years of daily data. In southeast Florida, the lunar nodal cycle has a total amplitude of approximately 2.1 inches (5.3 cm) and arises due to the precession of the moon’s orbital plane relative to the sun’s plane; it was calculated using a multiple linear regression of the detrended daily data [3].  When the LNC is on an upward swing, its effects are added to the background sea level rise, creating an apparent very rapid rise in a few years. Similarly, when the LNC is on a downward swing, it can nearly counteract the background sea level rise creating an apparent stagnation for several years.  But, it is important to look at long time series and to account for this cycle when calculating trends.  Aside from these regular cycles, local sea level is influenced by land-based ice melt, thermal expansion of the ocean as it warms, the strength of the Gulf Stream ocean current, among others.

Once the mean, seasonal cycle, and lunar nodal cycle are accounted for and removed from the daily water level dataset, we can calculate a linear trend.  Over the past 21 years, the average high tide has increased by roughly 0.25 inches/year, which is a slightly higher estimate compared to the trend shown in the first chart using annual averages (0.22 inches/year).

[This chart was updated in Jan 2017 and includes verified data through the end of 2016.]

[This chart was updated in Jan 2017 and includes verified data through the end of 2016.]

Be advised that simple linear trends of noisy time series are not reliable for extrapolating very far into the future, nor are the trend values reliable for shorter time periods.  Longer data records allow for greater confidence in a linear trend, but cannot account for accelerating rates.

Exposure

The Miami metropolitan region has the greatest amount of exposed financial assets and 4th-largest population vulnerable to sea level rise in the world.  The only other cities with a higher combined (financial assets and population) risk are Hong Kong and Calcutta [4].

Using a sea level rise projection of 3 feet by 2100 from the 5th IPCC Report [5] and elevation/inundation data, a map showing the resulting inundation is shown below.  The areas shaded in blue would be flooded during routine high tides, and very easily flooded by rain during lower tides.  Perhaps the forecast is too aggressive, but maybe not… we simply do not know with high confidence what sea level will do in the coming century.  But we do know that it is rising and showing no sign of slowing down.

Map showing areas of inundation by three feet of sea level rise, which is projected to occur by 2100. (NOAA)

Map showing areas of inundation by three feet of sea level rise, which is projected to occur by 2100. (NOAA)

An Attack from Below

In addition to surface flooding, there is trouble brewing below the surface too.  That trouble is called saltwater intrusion, and it is already taking place along coastal communities in south Florida. Saltwater intrusion occurs when saltwater from the ocean or bay advances further into the porous limestone aquifer.  That aquifer also happens to supply about 90% of south Florida’s drinking water.  Municipal wells pump fresh water up from the aquifer for residential and agricultural use, but some cities have already had to shut down some wells because the water being pumped up was brackish (for example, Hallandale Beach has already closed 6 of its 8 wells due to saltwater contamination [6]).

Schematic drawing of saltwater intrusion. Sea level rise, water use, and rainfall all control the severity of the intrusion. (floridaswater.com)

Schematic drawing of saltwater intrusion. Sea level rise, water use, and rainfall all control the severity of the intrusion. (floridaswater.com)

The wedge of salt water advances and retreats naturally during the dry and rainy seasons, but the combination of fresh water extraction and sea level rise is drawing that wedge closer to land laterally and vertically.

In other words, the water table rises as sea level rises, so with higher sea level, the saltwater exerts more pressure on the fresh water in the aquifer, shoving the fresh water further away from the coast and upward toward the surface.

Map of the Miami area, where colors indicate the depth to the water table. A lot of area is covered by 0-4 feet, including all of Miami Beach. (Dr. Keren Bolter)

Map of the Miami area, where colors indicate the depth to the water table. A lot of area is covered by 0-4 feet, including all of Miami Beach. (Dr. Keren Bolter, Center for Environmental Studies)

An Ever-Changing Climate

To gain perspective on the distant future, we should examine the distant past.  Sea level has been rising for about 20,000 years, since the last glacial maximum.  There were periods of gradual rise, and periods of rapid rise (likely due to catastrophic collapse of ice sheets and massive interior lakes emptying into the ocean). During a brief period about 14,000 years ago, “Meltwater Pulse 1A”, sea level rose over 20 times faster than the present rate. Globally, sea level has already risen about 400 feet, and is still rising.

Observed global sea level over the past 20,000 years... since the last glacial maximum. (Robert Rohde, Berkeley Earth).

Observed global sea level over the past 20,000 years… since the last glacial maximum. (Dr. Robert Rohde, Berkeley Earth).

With that sea level rise came drastically-changing coastlines.  Coastlines advance and retreat by dozens and even hundreds of miles as ice ages come and go (think of it like really slow, extreme tides).  If geologic history is a guide, we could still have up to 100 feet of sea level rise to go… eventually.  During interglacial eras, the ocean has covered areas that are quite far from the coastline today.

Florida's coastline through the ages. (Florida Geological Survey)

Florida’s coastline through the ages. (Florida Geological Survey)

As environmental author Rachel Carson stated, “to understand the living present, and promise of the future, it is necessary to remember the past”.

What Comes Next?

In the next 20 years, what should we reasonably expect in southeast Florida?  Using observed linear trends, sea level could be around 5 inches higher in 2034, but a realistic range is more like 5-9 inches.

Year by year, flooding due to heavy rain, storm surge, and high tides will become more frequent and more severe.  Water tables will continue to rise, and saltwater intrusion will continue to contaminate fresh water supplies.

This is not an issue that will simply go away.  Even without any additional anthropogenic contributions, sea level will continue to rise, perhaps for thousands of years.  But anthropogenic contributions are speeding up the process, giving us less time to react and plan.

Coastal cities were built relatively recently, without any knowledge of or regard for rising seas and evolving coastlines.  As sea level rises, coastlines will retreat inward. Sea level rise is a very serious issue for civilization, but getting everyone to take it seriously is a challenge.  As Dutch urban planner Steven Slabbers said, “Sea level rise is a … storm surge in slow motion that never creates a sense of crisis”.  It will take some creative, expensive, and aggressive planning to be able to adapt in the coming decades and centuries.

—–

Special thanks to Dr. Keren Bolter and Dr. Shimon Wdowinski for their inspiration and assistance.

1. http://www.sciencedirect.com/science/article/pii/S0964569116300278

2. http://tidesandcurrents.noaa.gov/stationhome.html?id=8723214

3. http://www.jcronline.org/doi/abs/10.2112/JCOASTRES-D-11-00169.1

4. http://www.businessinsider.com/cities-exposed-to-rising-sea-levels-2014-4

5. http://www.climatechange2013.org/images/report/WG1AR5_Chapter13_FINAL.pdf

6. http://www.palmbeachpost.com/news/news/wall-of-saltwater-snaking-up-south-floridas-coast/nLxg8/

Aquaculture, alumni, and more…

The Future of Aquaculture

Juvenile Mahi-Mahi

Juvenile Mahi-Mahi

UM Rosenstiel School Professor of Marine Ecosystems and Society Daniel Benetti published an essay on the future of aquaculture in the current issue of The Journal of Ocean Technology.

“In the field of aquaculture, technology has evolved at an enormous pace during the last two decades. Advances in technology are allowing all of us involved in the field, from scientists to operators, to address and tackle most, if not all, contentious issues in aquaculture.”

“Modern aquaculture relies on advanced technologies to produce wholesome seafood for human consumption. Indeed, aquaculture has become as important as farming and agriculture, currently contributing over 50% of wholesome seafood for human consumption worldwide. Aquaculture production continues to increase exponentially and is the fastest growing food production sector, having surpassed beef production in 2012-13 (66 million metric tons vs. 63 million metric tons). “

Read Dr. Benetti’s article in the JOT issue titled “Changing Tides in Ocean Technology,” (Volume 9 Number 2 (Jul. – Oct. 2014), An electronic subscription is required for full access to the issue.

Award-winning Student

MPO student Jie He

Jie He

UM Rosenstiel School Ph.D student Jie He was recently awarded “Outstanding Presentation for Students and Early Career Scientists” at the 7th International Scientific Conference on the Global Water and Energy Cycle, which took place in the Hague, Netherlands in July 2014. He is a Meteorology and Physical Oceanography  student studying the role of sea surface temperature pattern change in a warming climate in  Professor Brian Soden’s lab.

 

Alumnus Appoint President of Penn State University

Eric  J. Barron

Eric J. Barron

UM Rosenstiel School alumnus Eric Barron recently took the helm as president of Penn State University. Barron received his Master of Science (’76) and Ph.D (’80) in oceanography from the UM Rosenstiel School. In addition, he spent one year as an associate professor at UM before taking up a new post at the National Center for Atmospheric Research in Boulder, Colorado.

Barron has a distinguished resume, as the former President of Florida State University he lead the university’s rise to a U.S. News & World Report ranking as the most efficiently operated university in the nation. His expertise in the areas of climate, environmental change and oceanography, among other earth science topics, have led to extensive service for the federal government and the international community. Read more on about Penn State’s new president here.

 

 

Researchers Take to the Skies to Study Earth’s Climate

UM Rosenstiel School co-principal investigator Elliot Atlas (standing) during 2012 ATTREX mission.

UM Rosenstiel School co-principal investigator Elliot Atlas (standing) during 2012 ATTREX mission.

UM Rosenstiel School of Marine and Atmospheric Science professor Elliot Atlas recently returned from the two-month long CONTRAST (Convective Transport of Active Species in the Tropics) field experiment in the western Pacific Ocean. The research study focused on understanding the climate impact of trace gases transported from the ocean surface, up through a chimney of clouds and into the upper atmosphere.

Atlas, a professor of atmospheric chemistry, was a co-principal investigator of the first-of-its-kind National Science Foundation-funded research project into the chemistry of the tropical atmosphere.

Atlas is interested in trace gases that are linked to the formation and destruction of ozone in different layers of Earth’s atmosphere.  In the upper part of the atmosphere, known as the stratosphere, ozone absorbs much of the harmful UV radiation coming from the sun.  In the lower atmosphere, the presence of ozone is critical to facilitate the natural processes that cleanse the air of harmful pollutants.  In the region where the lower and upper atmosphere meet, ozone acts as a greenhouse gas and its abundance can be linked to global climate change.

The thickness of the ozone layer varies worldwide, being smaller at the equator and bigger near the poles. The ozone layer has been depleted in recent years due to large quantities of man-made compounds, including the most well known, the aerosol sprays containing CFCs.

Ozone Depleted

Members of the CONTRAST, CAST, and ATTREX research teams. Credit: NCAR

Members of the CONTRAST, CAST, and ATTREX research teams. Credit: NCAR

One question Atlas and his co-investigators Ross Salawitch from the University of Maryland and Laura Pan from the National Center for Atmospheric Research (NCAR), are trying to answer is, “what controls the abundance and variation of ozone in the atmosphere?”

To get closer to the answer, the CONTRAST team took to the sky to study the chemistry of clouds half a world away – in Guam. Understanding how atmospheric gases contribute to ozone abundances, and therefore Earth’s overall radiation budget from the sun, is critical for scientists to improve global climate change models.

“When you press on one side of the climate system, you get a response somewhere else,” says Atlas, explaining how seemingly different environments are linked in the global climate system.

View of convective clouds at 14 Km from one of the CONTRAST research flights. Credit: Laura Pan

View of convective clouds at 14 Km from one of the CONTRAST research flights. Credit: Laura Pan

A unique cluster of convective clouds – a virtual global chimney – forms over the western Pacific Ocean and is particularly intense during the winter in the Northern Hemisphere.  The tropical chimney is key to determining the chemical composition of the air entering the stratosphere. Huge clusters of thunderstorms feed heat and moisture as well as gases and particles into the upper atmosphere and eventually into the stratosphere, where they can influence climate on a global scale.

Of particular interest to Atlas and his UM-based research team is the role of chemicals containing bromine. Bromine-containing chemicals are emitted into the atmosphere from two distinct sources – a man-made source, which include compounds commonly used in fire extinguishers and can remain in the atmosphere for decades, and a natural source of short-lived compounds produced by tiny marine organisms in the ocean.

The bromine component of these chemicals can rapidly react with ozone as the compounds decompose in the atmosphere. Man-made bromides leave long-lived fingerprints that can be easily identified. What UM Rosenstiel School scientists are investigating are the poorly understood natural bromine concentrations from the ocean that is lofted into the atmosphere through the tropical chimney.

UM Rosenstiel School post-doctoral researcher Maria Navarro monitoring in-flight data collection.

UM Rosenstiel School post-doctoral researcher Maria Navarro monitoring in-flight data collection.

Atlas, and his UM research team, which included post-doctoral researcher Maria Navarro and research fellow Valeria Donets, took to the sky to study the trace gases in the atmosphere that are produced in high amounts by marine organisms in the warm tropical waters of the western Pacific.

“We want to know what happens to the bromine contained in gases from marine organisms when they are moved by clouds from the near the ocean surface up to the boundary of the stratosphere, over 9 miles up,” says Atlas.

Taking Flight

Stainless steel air sample canisters installed inside the NSF G-V aircraft to analyze trace gases.

Stainless steel air sample canisters installed inside the NSF G-V aircraft to analyze trace gases.

To collect bromine-containing gases, Atlas and colleagues built a specially designed instrument to fly onboard the NSF’s Gulfstream G-V aircraft during the 16 eight-hour CONTRAST flights. The aircraft flew at an altitude ranging from 0.5-15 km (0.2-9 miles), well above the limits of commercial airplanes, during January and February of 2014. The high altitude capabilities of this aircraft allowed the large team of scientists and engineers from multiple universities and research organizations participating in the project to study a critical part of the upper atmosphere that was unreachable by previous research aircraft.

To study the various chemical and physical components of the chimney cloud and the surrounding air, the aircraft was outfitted inside and out with state-of-the-art equipment that measure the many gases and air particles in the skies as the aircraft flew through the atmosphere, along with other data to understand the state of the atmosphere during the flights. During each mission, researchers at the shore-based operation center on Guam watched as data streamed back in real time and they communicated with colleagues onboard the aircraft to make spur-of-the-moment decisions about where additional sampling should take place. While instruments on the aircraft were making real-time measurements, trace gases were also being collected in airtight canisters for further in-depth analysis back in Atlas’ lab.

Now that the scientists have returned to their home bases, the data collected during the mission will be further analyzed and used to test how well current climate models depict cloud convection processes and the chemical composition of the tropical atmosphere, with a goal of improving how climate models predict future climate changes.

CONTRAST was conducted in collaboration with two other field experiments to take a comprehensive look at the entire region – the UK-led CAST (Coordinated Airborne Studies in the Tropics) experiment flew an instrument-laden aircraft to perform detailed studies in the atmosphere from near the ocean surface up to 6 km (3.7 mi), while the high-altitude ATTREX (Airborne Tropical Tropopause Experiment) mission using NASA’s Global Hawk unmanned drone studied the chemistry and physics of the atmosphere from 14-19 km (9-12 mi) altitude. The NSF G-V aircraft overlapped the study regions of the other two aircraft and sampled near the altitude of the outflow of the tropical cloud chimney.

“These combined aircraft measurements will provide an unprecedented description of the tropical atmosphere, from the ocean surface to the lower stratosphere, which will ultimately improve our current understanding of the atmosphere and our ability to make predictions about the role of atmospheric chemistry and tropical convection in a future climate,” said Atlas.

–Annie Reisewitz