Nav: Home

Geologic evidence is the forerunner of ominous prospects for a warming earth

October 12, 2017

Philadelphia, PA, October 12, 2017 - While strong seasonal hurricanes have devastated many of the Caribbean and Bahamian islands this year, geologic studies on several of these islands illustrate that more extreme conditions existed in the past. A new analysis published in Marine Geology shows that the limestone islands of the Bahamas and Bermuda experienced climate changes that were even more extreme than historical events. In the interest of our future world, scientists must seek to understand the complexities of linked natural events and field observations that are revealed in the geologic record of past warmer climates.

In Bermuda and the Bahamas, the geology of the last interglacial (LIG; approximately 120,000 years ago) is exquisitely preserved in nearly pure carbonate sedimentary rocks. A record of superstorms and changing sea levels is exposed in subtidal, beach, storm, and dune deposits on multiple islands. Extensive studies by the authors over the past decades on these islands have documented stratigraphic, sedimentologic, and geomorphic evidence of major oceanic and climatic disruptions at the close of the last interglacial.

Dr. Paul J. Hearty, a retired Associate Professor at the University of North Carolina at Wilmington, and Dr. Blair. R. Tormey, a Coastal Research Scientist at Western Carolina University conducted an invited review of published findings. It demonstrates that during a global climate transition in the late last interglacial, also known as marine isotope substage 5e (MIS 5e), abrupt multi-meter sea-level changes occurred. Concurrently, coastlines of the Bahamas and Bermuda were impacted by massive storms generated in the North Atlantic Ocean, resulting in a unique trilogy of wave-transported deposits: megaboulders, chevron-shaped, storm-beach ridges, and runup deposits on high dune ridges.

While perhaps more mundane than the megaboulders (found only locally on Eleuthera), the sedimentological structures found within chevron ridge and runup deposits across islands throughout the Bahamas and Bermuda point to frequent and repeated inundation by powerful storm waves, in some locations leaving storm deposits tens of meters above sea level.

During the last interglacial, sea levels were about 3-9 meters higher than they are now. The geologic evidence indicates that the higher sea-levels were accompanied by intense "superstorms," which deposited giant wave-transported boulders at the top of cliffed coastlines, formed chevron-shaped, storm beach ridges in lowland areas, and left wave runup deposits on older dunes more than 30 meters above sea level. These events occurred at a time of only slightly warmer global climate and CO2 (about 275 ppm) was much lower than today.

The authors emphasize "the LIG record reveals that strong climate forcing is not required to yield major impacts on the ocean and ice caps." In our industrial world, rapidly increasing atmospheric CO2 has surpassed 400 ppm, levels not achieved since the Pliocene era about 3 million years ago, while global temperature has increased nearly 1 °C since the 1870s. Today, ice sheets are melting, sea level is rising, oceans are warming, and weather events are becoming more extreme.

Drs. Hearty and Tormey conclude that with the greatly increased anthropogenic CO2 forcing at rates unmatched in nature, except perhaps during global extinction events, dramatic change is certain. They caution that, "Our global society is producing a climate system that is racing forward out of humanity's control into an uncertain future. If we seek to understand the non-anthropogenic events of the last interglaciation, some of the consequences of our unchecked forward speed may come more clearly into focus...a message from the past; a glimpse into the future."
Notes for Editors

The article is "Sea-level change and superstorms; geologic evidence from the last interglacial (MIS 5e) in the Bahamas and Bermuda offers ominous prospects for a warming Earth," by Paul J. Hearty and B.R. Tormey, ( It will appear in Marine Geology, volume 390, published by Elsevier. It is openly available online at

Full text of this article is available to credentialed journalists upon request. Contact Kristian Wilson at +44 1865 843817 or Journalists who wish to speak with the authors should contact Paul J. Hearty at or Blair R. Tormey at

About Marine Geology

Marine Geology is the premier international journal on marine geological processes in the broadest sense. It publishes papers that are comprehensive, interdisciplinary, and synthetic that will be lasting contributions to the field. Although most papers are based on regional studies, they demonstrate new findings of international significance. Papers cover subjects as diverse as seafloor hydrothermal systems, beach dynamics, early diagenesis, microbiological studies in sediments, palaeoclimate studies, and geophysical studies of the seabed.

About Elsevier

Elsevier is a global information analytics business that helps institutions and professionals progress science, advance healthcare and improve performance for the benefit of humanity. Elsevier provides digital solutions and tools in the areas of strategic research management, R&D performance, clinical decision support, and professional education; including ScienceDirect, Scopus, SciVal, ClinicalKey and Sherpath. Elsevier publishes over 2,500 digitized journals, including The Lancet and Cell, more than 35,000 e-book titles and many iconic reference works, including Gray's Anatomy. Elsevier is part of RELX Group, a global provider of information and analytics for professionals and business customers across industries.

Media contact

Kristian Wilson
+44 1865 843817


Related Sea Level Articles:

Researchers untangle causes of differences in East Coast sea level rise
For years, scientists have been warning of a so-called 'hot spot' of accelerated sea-level rise along the northeastern US coast, but understanding the causes has proven challenging.
Sea level as a metronome of Earth's history
Sedimentary layers contain stratigraphic cycles and patterns that precisely reveal the succession of climatic and tectonic conditions that have occurred over millennia.
Migration from sea-level rise could reshape cities inland
Researchers estimate that approximately 13.1 million people could be displaced by rising ocean waters.
Short-lived greenhouse gases cause centuries of sea-level rise
Even if there comes a day when the world completely stops emitting greenhouse gases into the atmosphere, coastal regions and island nations will continue to experience rising sea levels for centuries afterward, according to a new study by researchers at MIT and Simon Fraser University.
Climate change could trigger strong sea level rise
About 15,000 years ago, the ocean around Antarctica has seen an abrupt sea level rise of several meters.
Historical records may underestimate global sea level rise
New research from scientists at University of Hawai'i at Mānoa, Old Dominion University, and the NASA Jet Propulsion Laboratory shows that the longest and highest-quality records of historical ocean water levels may underestimate the amount of global average sea level rise that occurred during the 20th century.
Volcanic eruption masked acceleration in sea level rise
The cataclysmic 1991 eruption of Mount Pinatubo in the Philippines masked the full impact of greenhouse gases on accelerating sea level rise, according to a new study.
Pacific sea level predicts global temperature changes
Sea level changes in the Pacific Ocean can be used to estimate future global surface temperatures, according to a new paper in Geophysical Research Letters.
Climate change already accelerating sea level rise, study finds
Greenhouse gases are already having an accelerating effect on sea level rise, but the impact has so far been masked by the cataclysmic 1991 eruption of Mount Pinatubo in the Philippines, according to a new study led by NCAR.
As sea level rises, Hudson River wetlands may expand
In the face of climate change impact and inevitable sea level rise, Cornell and Scenic Hudson scientists studying New York's Hudson River estuary have forecast new tidal wetlands, comprising perhaps 33 percent more wetland area by the year 2100.

Related Sea Level Reading:

Sea Level
by Sea Level (Author)

Track: 1. Rain In Spain 6:47 2. Shake A Leg 3:53 3. Tidal Wave 5:40 4. Country Fool 3:40 5. Nothing Matters But The Fever 7:20 6. Grand Larceny 5:23 7. Scarborough Fair 5:31 8. Just A Good Feeling 3:01 View Details

Sea Level Rise in Florida: Science, Impacts, and Options
by Albert C. Hine (Author), Don P. Chambers (Author), Tonya D. Clayton (Author), Mark R. Hafen (Author), Gary T. Mitchum (Author)

“A scientifically credible and highly readable account of what is likely the greatest threat to Florida’s environment, economy, and culture over the coming decades.”—Reed F. Noss, author of Forgotten Grasslands of the South
“Every Floridian should read this book. It is the clearest and most readable description of how and why the sea level changes and what the future has in store for us.”—Orrin H. Pilkey, coauthor of Global Climate Change: A Primer
Sea levels are rising—globally and in Florida. Climatologists, geologists, oceanographers, and... View Details

Last Psalm at Sea Level
by Meg Day (Author)

Poetry. LGBT Studies. "Lovely does not suffice, nor does lyric. Eloquence is only a grasping in the space of ineffable air. There are few words or phrases that do justice to the soul singing its own revelations. That place is where LAST PSALM AT SEA LEVEL lives, where it is as solid as gold burning itself into light."—Afaa Michael Weaver View Details

DK Readers: Disasters at Sea (Level 3: Reading Alone)
by Andrew Donkin (Author)

From fog, ice, and rocks to cannon fire and torpedo attacks--read the story of five doomed sea voyages and the fate of those who took part in them. The 48-page Level 3 books, designed for children who can read on their own, contain more complex sentence structure and more detail. Young readers will devour these kid-friendly titles, which cover high-interest topics such as sharks, and the Bermuda Triangle, as well as classics like Aladdin. Information boxes highlight historical references, trivia, pronunciation, and other facts about words and names mentioned. Averaging 2,400 to 2,800 words,... View Details

from Sea level to C level
by E. Matthew Buckley (Author)

From Sea Level to C Level chronicles experiences seen through the eyes of former Navy fighter pilot, E. Matthew Buckley, call sign Whiz. The book is also written in the words of a man who turned his naval experience into a hugely successful career in corporate America. Drawing upon the Navy's unparalleled approach to planning, execution, strategy, and leadership, Whiz has created a unique set of tools men and women in any profession can use to drive their careers to new heights. Unlike other military personnel who have tried to tie the military and business worlds together, Whiz has "been... View Details

The Sedimentary Record of Sea-Level Change
by Angela L. Coe (Author), Dan W. J. Bosence (Author), Kevin D. Church (Author), Stephen S. Flint (Author), John A. Howell (Author), R. Chris L. Wilson (Author)

This illustrated textbook describes how past changes in sea-level can be detected through an analysis of the sedimentary record, and how sequence stratigraphy techniques can provide explanations of how the sedimentary system evolves through geological time. Designed for use in undergraduate and graduate courses, it includes detailed case studies, set-aside focus boxes, and bulleted Questions and Answers interspersed throughout. The book is also supported by a website hosting sample pages. View Details

Sea Level
by Nancy Kilgore (Author)

Brigid Peterson is the new minister in the remote seaside town of Sand Hill.  The year is 1980 and her parishioners are wary and even hostile to a woman in the pulpit.  She finds a kindred spirit in her new friend Mary Bradley, an artist who believes in the goddess.  But Mary has fallen hopelessly in love with a local drifter, and Brigid's marriage is beginning to crumble, and when Brigid preaches about the female side of God, the whole town divides over her.  Both women have to dive deeper into their spiritual life to find the way through.

Sea Level is a story about ordinary... View Details

Houghton Mifflin Social Studies: From Sea to Shining Sea Level 3
by Wixson Armento Nash Salter (Author)

Houghton Mifflin Social Studies: From Sea to Shining Sea Level 3 by Salter, Wixson Armento Nash Houghton Mifflin School View Details

Murder on the Levels: An Exham on Sea Mystery: Book Two (The Exham on Sea Mysteries) (Volume 2)
by Frances Evesham (Author)

Love cosy crime, murder mysteries, clever animals and chocolate? Don’t miss Murder on the Levels, the second Exham on Sea mystery, set in a seaside town in Somerset. Two cyclists die on the Somerset Levels, and the Exham bakery gets the blame. Libby Forest runs into danger as she sets out to solve the mystery, save the bakery and rescue her career, helped by Bear, the enormous Carpathian Sheepdog, Fuzzy, an aloof marmalade cat and the handsome, secretive Max Ramshore. Set in the coastal resort of Exham on Sea, Murder on the Levels features a cast of local characters, including Mandy the... View Details

Icky Sticky Readers: Splendid Sea Creatures (Scholastic Reader, Level 2)
by Laaren Brown (Author)

Explore everything awesome about sea creatures in a fun, accessible, and laugh-out-loud format! Find out awesome facts about all sorts of animals from under the sea -- including whales, sharks, fish, and more. Which animals are the prey and which are the hunters? Which animals can blend into plants and the ocean floor? And what other cool tricks do these awesome sea creatures know? Bursting with attention-grabbing facts, fun, and stickers, this reader will keep every child turning pages. View Details

Best Science Podcasts 2018

We have hand picked the best science podcasts for 2018. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

The Consequences Of Racism
What does it mean to be judged before you walk through the door? What are the consequences? This week, TED speakers delve into the ways racism impacts our lives, from education, to health, to safety. Guests include poet and writer Clint Smith, writer and activist Miriam Zoila Pérez, educator Dena Simmons, and former prosecutor Adam Foss.
Now Playing: Science for the People

#465 How The Nose Knows
We've all got a nose but how does it work? Why do we like some smells and not others, and why can we all agree that some smells are good and some smells are bad, while others are dependant on personal or cultural preferences? We speak with Asifa Majid, Professor of Language, Communication and Cultural Cognition at Radboud University, about the intersection of culture, language, and smell. And we level up on our olfactory neuroscience with University of Pennsylvania Professor Jay Gottfried.