Science Current Events | Science News | Brightsurf.com
 

Scientists core into California's Clear Lake to explore past climate change

May 04, 2012
Deep sediments are unparalleled record of biotic changes over past 200,000+ years

University of California, Berkeley, scientists are drilling into ancient sediments at the bottom of Northern California's Clear Lake for clues that could help them better predict how today's plants and animals will adapt to climate change and increasing population.

The lake sediments are among the world's oldest, containing records of biological change stretching back as far as 500,000 years.

The core drilling is part of a unique, multifaceted effort at UC Berkeley to determine how Earth's flora and fauna responded to past changes in climate in order to improve models that project how life on Earth will adapt to today's environmental pressures. What the researchers learn from their look-back in time will be crucial for state or local planners clamoring for better predictive tools to guide policies crucial to saving ecosystems threatened by climate change.

"We are reconstructing the past to better forecast the future, because we need to know what's coming in order to adequately prepare for it," said project leader Cindy Looy, UC Berkeley assistant professor of integrative biology.

Looy and 16 other UC Berkeley faculty members - including paleontologists, pollen experts, botanists, ecologists and climate modeling experts - will examine the lake cores for pollen grains, charcoal and fresh-water organisms going back at least 130,000 years, long before humans arrived in the area. Using isotope and chemical analysis as well as carbon dating, the researchers will obtain a long series of detailed snapshots - ideally, every 10 years - of the plant and animal communities in the Clear Lake area and how the communities changed in response to "natural" global warming events. The analysis will also provide a measure of the temperature, oxygen content and nutrient levels of the lake, which reflect rainfall and water level.

"One way to check our predictions is to go back in time to a state very similar to today, with the same plants and animals and about the same temperature. The fossilized plant and animal remains from Clear Lake will give us a baseline for what this region of California looked like under similar climatic conditions, and when it was colder or warmer. We use that information to fine-tune predictive models being developed today," Looy said. "Rates of global warming almost as fast as what we see today last happened during the shift from the last glacial to the current interglacial roughly 12,000 years ago, so that is one time intervals we will focus on."

Focusing on two glacial-to-interglacial transitions

Looy and her team also will look at an even earlier transition from a glaciated Earth 130,000 years ago to a time 113,000 years ago when it may have been locally warmer than today. Learning what the area looked like during that time will help Northern Californians anticipate how conditions will change as global temperature continues to rise over the coming decades.

"There are indications from ice cores and ocean drilling cores that the beginning of the previous interglacial may have been warmer than it is now, which is where it becomes interesting," said Looy. "We know what the Earth is like at today's temperature, but a lot of people are trying to predict what will happen if the earth warms 1 or 2 degrees Celsius (2-4 degrees Fahrenheit), or even more."

Charcoal in the lake sediments will also tell the researchers how Native Americans altered the environment through deliberate fires designed, for example, to increase acorn production by oaks.

One member of the team, Anthony Barnosky, UC Berkeley professor of integrative biology, will correlate this information with mammalian fossils collected from cave deposits in the area and that have been stored for decades in the Museum of Paleontology.

"You can view the core as a time machine by which we can define a continuous record of change, both climatic and vegetational, though the past 130,000 years, and then we have all these floating snapshots of the ecosystem - the mammal communities - from cave deposits around here," Barnosky said. "We can put names on these fossils and radiocarbon-date them and begin to build a 3-D picture of change through time from the late Pleistocene, some 130,000 years ago, through the last glacial/interglacial transition 13,000 to 11,000 years ago, all the way up to the present."

The study will help to evaluate and refine current models that predict how plants and animals will adapt to a changing world by testing predictions of the models against what actually happened during past times of climate change. Such models are important for state and local planning agencies that must deal with future consequences of climate change, including sea level rise, water shortages and increasing fire incidence that can threaten ecosystems.

"Based on this type of research at UC Berkeley, we want to make the case that adaptation to a changing climate is an issue we have to take more seriously, we have to bring it more into the mainstream of Bay Area planning," said Bruce Riordan, director of the Bay Area Joint Policy Committee, which coordinates regional planning agencies in responding to climate adaptation. "By starting planning now and understanding the problems, the strategies we need to implement and the costs involved, we may find less costly solutions today rather than later. The research can really help inform about both the problems and about the solutions."

Half million years of sediment

Clear Lake is unusual in having survived the advance and retreat of glaciers that scoured and obliterated most lakes outside the tropics, including the large lakes in California's Sierra Nevada. Previous coring in Clear Lake by the U.S. Geological Survey (USGS) in 1973 and 1980 revealed lake sediments half a million years old, with only three breaks in continuity. At the site where UC Berkeley plans to obtain cores, in the upper arm of the lake about 1-3 miles west southwest of the town of Lucerne, the USGS obtained a continuous core in 1973 going back 130,000 years.

Looy and her team hired Utah-based DOSECC (Drilling, Observation and Sampling of the Earths Continental Crust), a non-profit scientific drilling company, to obtain two 120 meter-long (400-foot) cores, each about 8 centimeters (3 inches) in diameter. The cores are obtained in 3-meter (10-foot) chunks that are capped and labeled at the site and will be shipped to a cold-storage facility in Minnesota operated by LacCORE (National Lacustrine Core Facility), a non-profit organization funded by the National Science Foundation and the University of Minnesota. In the facility's cold lab, the team will split each chunk longitudinally, photograph the halves, and then bring one half of each chunk back to UC Berkeley for analysis.

While the USGS sampled its cores once every meter, Looy and her team will sample parts of their cores every centimeter, the equivalent of about 10 years of sediment.

"We will get 100 times better time resolution, and can follow what happens when you rapidly warm the Earth up," Looy said.

"The detail we can get from Clear Lake is really impressive," she added. "The material is well preserved, and the USGS did a great job in describing the whole time interval so that now we know what the interesting areas are to focus on. We know this is not a shot in the dark."

###

The Clear Lake drilling project is one of seven research projects involving global change forecasting funded by a $2.5 million grant from the Gordon and Betty Moore Foundation to UC Berkeley's Berkeley Initiative in Global Change Biology, or BiGCB. Each project focuses on a particular California environment and leverages UC Berkeley's unique museum collections of vertebrates, insects, plants and fossils to provide details about past changes in plant and animal populations.

University of California - Berkeley


Related Climate Change Current Events and Climate Change News Articles


Is nuclear power the only way to avoid geoengineering?
To avoid the need for geoengineering, which could have enormous unforeseen consequences, the international community should pursue increased deployment of nuclear power plants, which do not emit carbon dioxide, to address the climate crisis.

Fiction prepares us for a world changed by global warming
Climate fiction, or simply cli-fi, is a newly coined term for novels and films which focus on the consequences of global warming.

Wildlife response to climate change is likely underestimated, experts warn
Analyzing thousands of breeding bird surveys sent in by citizen scientists across the western United States and Canada over 35 years, wildlife researchers report that most of the 40 songbird species they studied shifted either northward or toward higher elevation in response to climate change, but did not necessarily do both.

Lack of breeding threatens blue-footed boobies' survival
Blue-footed Boobies are on the decline in the Galápagos. A new study appearing in the journal Avian Conservation and Ecology indicates numbers of the iconic birds, known for their bright blue feet and propensity to burst into dance to attract mates, have fallen more than 50 percent in less than 20 years.

Earth Week: Bark beetles change Rocky Mountain stream flows, affect water quality
On Earth Week--and in fact, every week now--trees in mountains across the western United States are dying, thanks to an infestation of bark beetles that reproduce in the trees' inner bark.

Minnesota projects offer hope and practical help to communities facing more extreme storms
Recent projects in two Minnesota cities demonstrate how communities can protect themselves from worsening storms. These projects continue a ten year program in New England and the Midwest providing practical and affordable plans tailored to local conditions.

Plants with dormant seeds give rise to more species
Seeds that sprout as soon as they're planted may be good news for a garden. But wild plants need to be more careful. In the wild, a plant whose seeds sprouted at the first warm spell or rainy day would risk disaster.

Researchers Find 3-million-year-old Landscape Beneath Greenland Ice Sheet
Glaciers and ice sheets are commonly thought to work like a belt sander. As they move over the land they scrape off everything - vegetation, soil and even the top layer of bedrock.

Stanford researchers rethink 'natural' habitat for wildlife
Protecting wildlife while feeding a world population predicted to reach 9 billion by 2050 will require a holistic approach to conservation that considers human-altered landscapes such as farmland, according to Stanford researchers.

More questions than answers as mystery of domestication deepens
We all think we have a rough idea of what happened 12,000 years ago when people at several different spots around the globe brought plants under cultivation and domesticated animals for transport, food or fiber. But how much do we really know?
More Climate Change Current Events and Climate Change News Articles

Climate Change: Evidence and Causes (PDF Booklet)

Climate Change: Evidence and Causes (PDF Booklet)
by National Academies Press


Climate Change: Evidence and Causes is a jointly produced publication of The US National Academy of Sciences and The Royal Society. Written by a UK-US team of leading climate scientists and reviewed by climate scientists and others, the publication is intended as a brief, readable reference document for decision makers, policy makers, educators, and other individuals seeking authoritative information on the some of the questions that continue to be asked. Climate Change makes clear what is well-established and where understanding is still developing. It echoes and builds upon the long history of climate-related work from both national academies, as well as on the newest climate-change assessment from the United Nations' Intergovernmental Panel on Climate Change. It touches on current...

The Climate Crisis: An Introductory Guide to Climate Change

The Climate Crisis: An Introductory Guide to Climate Change
by David Archer (Author), Stefan Rahmstorf (Author)


An incredible wealth of scientific data on global warming has been collected in the last few decades. The history of the Earth's climate has been probed by drilling into polar ice sheets and sediment layers of the oceans' vast depths, and great advances have been made in computer modeling of our climate. This book provides a concise and accessible overview of what we know about ongoing climate change and its impacts, and what we can do to confront the climate crisis. Using clear and simple graphics in full color, it lucidly highlights information contained in the Intergovernmental Panel on Climate Change reports, and brings the subject completely up-to-date with current science and policy. The book makes essential scientific information on this critical topic accessible to a broad...

Climate Change: Evidence, Impacts, and Choices

Climate Change: Evidence, Impacts, and Choices
by National Academies Press


What is climate? Climate is commonly thought of as the expected weather conditions at a given location over time. People know when they go to New York City in winter, they should take a heavy coat. When they visit the Pacific Northwest, they should take an umbrella. Climate can be measured as many geographic scales - for example, cities, countries, or the entire globe - by such statistics as average temperatures, average number of rainy days, and the frequency of droughts. Climate change refers to changes in these statistics over years, decades, or even centuries.  Enormous progress has been made in increasing our understanding of climate change and its causes, and a clearer picture of current and future impacts is emerging. Research is also shedding light on actions that might be taken...

The Rough Guide to Climate Change (Rough Guide Reference Series)

The Rough Guide to Climate Change (Rough Guide Reference Series)
by Robert Henson (Author)


"The Rough Guide to Climate Change" gives the complete picture of the single biggest issue facing the planet. Cutting a swathe through scientific research and political debate, this completely updated 3rd edition lays out the facts and assesses the options - global and personal - for dealing with the threat of a warming world. The guide looks at the evolution of our atmosphere over the last 4.5 billion years and what computer simulations of climate change reveal about our past, present and future. This updated edition includes scientific findings that have emerged since the 2007 report from the Intergovernmental Panel on Climate Change (IPCC), as well as background on recent controversies and an updated politics section that reflects post-Copenhagen developments. You can discover how...

Climate Change: Picturing the Science

Climate Change: Picturing the Science
by Gavin Schmidt (Author), Joshua Wolfe (Author), Jeffrey D. Sachs (Foreword)


An unprecedented union of scientific analysis and stunning photography illustrating the effects of climate change on the global ecosystem. Going beyond the headlines, this work by leading NASA climate scientist Gavin Schmidt and master photographer Joshua Wolfe illustrates as never before the ramifications of shifting climate. Photographic spreads show retreating glaciers, sinking villages in Alaska’s tundra, and drying lakes. The text follows adventurous scientists through the ice caps at the poles to the coral reefs of the tropical seas. Marshaling data spanning centuries and continents, the book sparkles with cutting-edge research and visual records, including contributions from experts on atmospheric science, oceanography, paleoclimatology, technology, politics, and the polar...

Climate Change: What the Science Tells Us

Climate Change: What the Science Tells Us
by Charles Fletcher (Author)


Fletcher's 1st edition of "Climate Change: What the Science Tells Us" places strong emphasis on the peer-reviewed literature in reporting the impacts of climate change on the ocean, terrestrial ecosystems, the water cycle, human communities, dangerous weather patterns, and potential future Earth systems. The book offers detailed discussion of greenhouse gases, oceanic and atmospheric processes, Pleistocene and Holocene paleoclimate, the human fingerprints of climate change, modeling climate, sea level rise, climate impacts on economic sectors, and dangerous weather patterns associated with climate change.Fletcher offers the first real textbook to present the science surrounding climate change at the right level for an undergraduate student. His polished writing style makes this an...

Global Warming: Alarmists, Skeptics & Deniers; A Geoscientist looks at the Science of Climate Change

Global Warming: Alarmists, Skeptics & Deniers; A Geoscientist looks at the Science of Climate Change
by Moonshine Cove Publishing, LLC


“The author makes it very clear that a changing climate is not unusual. It is in fact the norm -- although change is often so slow that humans cannot detect it directly.  But historical geologists know how to display the evidence to the public. This may be the single most important contribution of this well-written and fact-filled book.”—Dr. S. Fred Singer, Chairman Science & Environmental Policy Project

“Global Warming: Alarmists, Skeptics and Deniers is a refreshing read on a topic of great societal importance; refreshing because, unlike many books published on this subject, the authors of this work evaluate key predictions and controversies of the global warming debate using logic and science.  Most readers will appreciate the book’s arrangement.  Each chapter...

Climate Change 2013 - The Physical Science Basis: Working Group I Contribution to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change

Climate Change 2013 - The Physical Science Basis: Working Group I Contribution to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change
by Intergovernmental Panel on Climate Change (Editor)


This latest Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC) will again form the standard scientific reference for all those concerned with climate change and its consequences, including students and researchers in environmental science, meteorology, climatology, biology, ecology and atmospheric chemistry. It provides invaluable material for decision makers and stakeholders: international, national, local; and in all branches: government, businesses, and NGOs. This volume provides: • an authoritative and unbiased overview of the physical science basis of climate change; • a more extensive assessment of changes observed throughout the climate system than ever before; • new dedicated chapters on sea-level change, biogeochemical cycles, clouds and...

The Whole Story of Climate: What Science Reveals About the Nature of Endless Change

The Whole Story of Climate: What Science Reveals About the Nature of Endless Change
by E. Kirsten Peters (Author)


In the publicity surrounding global warming, climate scientists are usually the experts consulted by the media. We rarely hear from geologists, who for almost two hundred years have been studying the history of Earth's dramatic and repeated climate revolutions, as revealed in the evidence of rocks and landscapes. This book, written by a geologist, describes the important contributions that geology has made to our understanding of climate change. What emerges is a much more complex and nuanced picture than is usually presented.

While the average person often gets the impression that the Earth's climate would be essentially stable if it weren't for the deleterious effects of greenhouse gases, in fact the history of the earth over many millennia reveals a constantly changing climate....

Storm Warnings: Climate Change and Extreme Weather

Storm Warnings: Climate Change and Extreme Weather
by Scientific American


Hurricanes. Blizzards. Flooding. Drought. If extreme events like these seem to be on the rise, it’s for apparent reason. The first three-quarters of 2012 brought the worst European winter in 25 years; massive flooding in Australia, Brazil and China; a deepening drought affecting over 50% of the US; and Hurricane Sandy inflicted massive damage on the Northeast US. The likelihood of these extreme weather events are increasingly being tied to anthropogenic—or manmade, mostly through overproduction of carbon dioxide—global warming. It’s no longer an abstract idea; it’s being felt locally, on every level.
This eBook, Storm Warnings: Climate Change and Extreme Weather, gives you the tools to better understand what’s behind climate change, what might be in store during the coming...

© 2014 BrightSurf.com