Students Collaborate on One-of-a-kind Coral Bleaching Study

Thanks to an award from the Rosenstiel School’s Graduate Career Development Fund, a collaborative, graduate student-led research team has a one-of-a-kind opportunity to study how corals recover from mass bleaching events.

Five students – Jay Fisch, Erica Towle, Crawford Drury, Phil Kushlan and Rivah Winter – from three different labs across the Rosenstiel School campus have come together to design and execute a field study of an important reef-building coral, Orbicella faveolata, commonly known as Mountainous Star Coral, that suffered during the widespread coral bleaching event at Horseshoe Reef in the Florida Keys during the summer of 2014.

RSMAS graduate students: Phil Kushlan, Erica Towle, Crawford Drury, Jay Fisch, and Rivah Winter

RSMAS graduate students (from left to right): Phil Kushlan, Erica Towle, Crawford Drury, Jay Fisch, and Rivah Winter

Historic information previously collected at the site, combined with collections over the next year will allow the student team to study changes in coral symbiosis and metabolism and to measure individual colony response and recovery following a bleaching event. The research project will provide scientists with valuable new information on the relationship between recovery patterns and subsequent reproductive output.

“Recovery of reefs depends on both the recovery of the surviving individuals as well as the input of new individuals through reproduction,” said the students.

The students received a total of $3000 from the Graduate Career Development Fund. The students are Ph.D. candidates in Lirman’s Benthic Ecology Lab, Baker’s Coral Reef and Climate Change Lab and Langdon’s Coral and Climate Change Lab.

Rescue a Reef Update

130813_112247_054_CoralRestoration Coral reef with out planted stag horn corals.

It’s been over 2 years since Dr. Diego Lirman’s Benthic Ecology Lab at RSMAS began outplanting nursery reared staghorn corals (Acropora cervicornis) to degraded reefs as part of one of the largest Acropora restoration projects along the Florida Reef Tract. Today, those corals are making a significant impact on the structure and function of Miami’s reefs.

The University of Miami Rosenstiel School of Marine and Atmospheric Science began growing colonies of the threatened staghorn coral in underwater nurseries starting with only 200 small fragments collected from existing wild colonies. To date, UM’s nurseries have produced over 6,000 healthy corals. Beginning in 2012, over 2,500 staghorn corals were carefully transplanted to their new homes on local reefs in Miami-Dade County. Over 85% of outplanted corals have survived to become part of the natural habitat and have grown to equal 243 meters of new staghorn! That is over 603% more coral than was originally outplanted! This is a significant increase in the number of Acropora colonies on local reefs and will help bridge spatial gaps between existing populations to enhance sexual reproduction and genetic diversity.The Benthic Ecology Lab has learned valuable lessons from their initial restoration success and has developed methods and techniques to increase the survival and growth of outplanted corals. In addition, important informtion about nursery and outplant site selection, growth and productivity variation between genotypes, effects of predation, and recovery from bleaching have been investigated to provide researchers and managers with essential conservation tools for the recovery of threatened staghorn corals.

–Stephanie Schopmeyer, Senior Research Associate II, Lirman Lab

N In Plot 3 P46 Initial size of staghorn coral fragment outplanted in 2012 (5 cm)

IMG_1360-1 Growth of staghorn coral two years after outplanting onto local reef (390 cm)

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/

UM coral scientist studies at Centre Scientifique de Monaco

As I write this blog, I am looking out the window at the famous Port Hercule in Monaco and see all of the beautiful yachts and racing sailboats.  And the best part is – I’m in my office!  Allow me to back-track: I am a 5th year Ph.D. candidate in Dr. Chris Langdon’s lab here at RSMAS.  I study indicators of resilience to climate change stressors in Florida Reef Tract corals.  Two years ago I met Dr. Christine Ferrier-Pages at the International Coral Reef Symposium.  Christine is the director of the Coral Eco-physiology team at the Centre Scientifique de Monaco (CSM), and I have admired her work on coral feeding for years.  By maintaining contact with her after we met at the conference, and through another colleague of Chris Langdon’s at a French university, I was offered the opportunity to participate in a seven-week collaboration in Christine’s lab in Monaco.  Together, we are studying the combined effects of nutrient enrichment (eutrophication), coral feeding, and elevated temperature stress on coral growth and physiology.  The lab facilities here are unparalleled, and it is truly an honor and a privilege for me to complete the last chapter of my dissertation at this institution.

View of Port Hercule in Monaco

View of Port Hercule in Monaco

Here’s a little history about CSM: it was founded in 1960 at the request of Prince Rainier III, Prince of Monaco, to provide the Principality of Monaco with the means of carrying out oceanographic research and to support governmental and international organizations responsible for the protection and conservation of marine life.  Since the late 1990s, the CSM has been a leader in coral reef biology, specializing in biomineralization research and climate change effects on corals.  The ocean and the issues surrounding it have always been on the forefront of causes important to the royal family of Monaco.  In addition to the CSM, Monaco also boasts an extensive oceanography museum and aquarium which draws international attention.

So what has it been like to work here so far?  One thing I have found a little challenging is learning to run an experiment in another language.  While most of the researchers here speak English (their publications are normally submitted in English,) French is their native language and is most commonly spoken in the lab.  I speak conversational French pretty well, but I have to learn basic experiment terms in French; words like tubes, flow rate, and probe, to name a few, were all new to me in the French language.

For now, my post-work view is the Mediterranean Sea, but I know in a few weeks a sunset view overlooking Biscayne Bay from the Wetlab patio will be calling my name…

Until then,

Erica Towle, Ph.D. Candidate, Marine Biology and Ecology

 

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.

 

 

Scientific Drones Help Understand Formation of Bahamas Islands

University of Miami graduate student Kelly Jackson and Camera Wings Aerial Photography recently teamed up to capture high-resolution photographs of remote islands in the Bahamas using specially equipped drones. The study is aimed at finding new ways to more precisely study the geological evidence preserved inside bedrock during critical events in Earth’s history.

The UM Rosenstiel School and Camera Wings Aerial Photography teams prepare to launch a drone

The UM Rosenstiel School and Camera Wings Aerial Photography teams prepare to launch a drone. From left to right: Robert Youens (CW), Brent Hall (CW) Gregor Eberli (UM), Kelly Jackson (UM), and Mitch Harris (UM).

“Drones are changing the way geologists map,” said Jackson, a Ph.D. student in the Marine Geology and Geophysics program at the UM Rosenstiel School of Marine and Atmospheric Science. “It is now possible to acquire high-resolution photographs and elevation data of the hardest to reach locations.”

From the deck of the John G. Shedd Aquarium’s research vessel R/V Coral Reef II, Jackson and her team launched this unmanned aircraft outfitted with high-resolution digital cameras and position loggers over the remote islands of the Exuma Cays. Their goal of the study is to look back in time at the formation of the islands, which was driven by rapid fluctuations in sea level 125,000 years ago during the Pleistocene.

A drones-eye view of the Bahamas.

A drones-eye view of the Bahamas.

Using this newly available data from the drone technology, scientists can develop more detailed 3-D maps of the complex carbonate deposits, which holds important information about what Earth was like during the last interglacial period, when warmer global temperatures caused glacial melting.

Jackson and her team are currently analyzing the data obtained from the drone mapping survey.

A drone captures a photo of the research team below.

A drone captures a photo of the research team below.

— Annie Reisewitz 

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