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Showing posts with label OCEAN ACIDIFICATION. Show all posts
Showing posts with label OCEAN ACIDIFICATION. Show all posts

New study finds Alaskans familiar with ocean acidification, not aware of risks to fisheries

New research published in Marine Policy from the first Alaska-focused study on public understanding and awareness of ocean acidification risk shows that Alaskans are three times more aware of ocean acidification than Americans in general.  However, Alaskans have difficulty seeing ocean acidification as an immediate risk, and the direct risks to Alaska’s fisheries are still not well understood. The research, “Gauging perceptions of ocean acidification in Alaska,” can be read online.

In Alaska, the impacts of ocean acidification have the potential to be even worse than “other coastal communities because of an accelerated rate of change in ocean chemistry, and statewide reliance on commercial and subsistence fishing. Accurately evaluating ocean acidification risk directly influences the ability to respond to change. The research builds on earlier NOAA-led research showing that communities in southeast and southwest Alaska are more at risk than other areas of the state because of their heavy reliance on fisheries expected to be impacted by ocean acidification.

“We wanted to learn the best way to provide Alaskans with the information they need to properly respond to ocean acidification,” said Lauren Frisch, who led the study and is a research associate at the University of Alaska Fairbanks Ocean Acidification Research Center. “The first step was to determine where there are gaps in the understanding of ocean acidification so that we can then work to fill them in.”
                      Crab fishing
A new study shows that Alaskans know about ocean acidification, but are not aware of the risk it poses to Alaskan fisheries. (NOAA)

Some 2000 Alaskans received a questionnaire in September, 2013. Questionnaires asked about each respondent’s role in the state's fishing industry as well as their belief in, understanding of, and concern about ocean acidification. The questionnaire’s response rate was 18 percent, which is high for studies of this nature. Results showed limited understanding of how Alaska will be uniquely impacted by ocean acidification. For example, only 28 percent of Alaskans believe that ocean acidification would have a greater impact on Alaska than other states in the United States.  Alaskans affiliated with the state’s fishing industry are not significantly more concerned about ocean acidification than those unaffiliated, and only 33 percent believe that ocean acidification will decrease revenue for fisheries. Finally, ocean acidification is perceived as a distant risk.  

“It can be difficult to think about ocean acidification as an immediate risk with all of the other challenges that we’re facing,” said Jeremy Mathis, who is the co-lead author on the paper describing the study’s results and an oceanographer at NOAA’s Pacific Marine Environmental Laboratory. “We really have to work harder to get the message out to stakeholders around Alaska that ocean acidification is something that they need to consider sooner rather than later.”

With a better idea of what Alaskans understand about this issue, the next step is to shape public education in a way that facilitates a long-term discussion of ocean acidification drivers and impacts, as well as mitigation and adaptation strategies.

“Moving forward, we need to figure out how to enhance this understanding that acidification is not uniform, and therefore adaptation plans will be more successful if they are local.  Educating communities with local examples about their specific risk could help foster this understanding.  The best thing we can do is provide vulnerable communities the toolset to evaluate risk themselves,” said Frisch.

Source: NOAA

NOAA’s investments in weather models and partnerships paying off

Early improvements effective in forecasting recent Nor’easter; future forecast model upgrades planned
As the Northeast digs out from this week’s blizzard, a new NOAA-led effort to improve the forecasting of such high impact weather events is reaching an important early benchmark. One of the first major improvements - upgrading the resolution of three global forecast models -- has already shown its effectiveness. One of these models, the newly upgraded Global Forecast System (GFS) model, provided one of the most precise forecasts of the track, intensity, precipitation, and distribution of the Nor’easter. The other research models provided important forecast information, as well.

“The Global Forecast System did remarkably well in the recent Nor’easter,” said Louis Uccellini, director of NOAA’s National Weather Service. “This is due to the recent improvements we’ve made to the GFS, including higher resolution, improved physics, and better access to new data. With the help of scientists at NOAA Research, we’re making improvements to all our models, and upgrading supercomputers to improve our ability to translate data into actionable information, and to produce more timely, accurate and reliable forecasts.”

By the end of January, the $13 million project called the High Impact Weather Prediction Project (HIWPP), funded by Congress in the wake of Hurricane Sandy, will have improved the resolution on the global forecast model operated by NOAA Research Earth System Research Laboratory and the model operated by the U.S. Navy.
Improving global models
Scientists at NOAA’s Earth System Research Laboratory are running a high resolution global forecast model called the FIM, or Flow following finite volume Icoschedral Model. As depicted here, the FIM uses a unique grid that allows for a more uniform representation of the Earth. Higher resolution models are helping improve severe weather prediction. (NOAA)

In addition, NOAA researchers have written and installed programs to enable these three global models to work together effectively, which provides greater accuracy and confidence in forecasts. The third improvement is a plan to actively involve the broader weather forecasting community, including other public, academic and private sector scientists, in the evaluation of how these models work together to refine and improve forecasts.

“We are always looking for ways to improve the reliability and accuracy of our forecasts and models,” said John Cortinas, director of NOAA’s Office of Weather and Air Quality, who is overseeing HIWPP, which involves researchers from NOAA’s Oceanic and Atmospheric Research, NOAA’s National Weather Service, cooperative institutes, other government and academic partners.

“The goal of the project is to develop the next generation of weather forecast models that will eventually extend our ability to skillfully forecast high-impact weather out to several weeks and beyond,” Cortinas said. “By extending lead time for forecasts on storms like the one we’ve just experienced, cities and towns can better plan for these events, potentially saving lives and helping protect valuable land, homes and businesses. Businesses and industry can better plan everything from shipping to safe routing of air traffic to energy consumption. For ordinary citizens, it will be easier to plan an event or a trip.”

Over the last decades, weather forecasts have improved steadily so that we now have accurate forecasts out to five days, with reasonable accuracy to seven days. “We’ve gained about a day a decade in accuracy,” said Timothy Schneider, a research meteorologist at NOAA’s Earth System Research Laboratory, who is working to improve global forecast models. “Gaining a day of accuracy involves a combination of improving the science, adding computer power and increasing the necessary observations. With this project, we’re trying to accelerate this progress to make quicker gains.”

Global weather data key to improved local forecasts

“We know we can get better weather forecasts by improving the resolution of global forecast models so they depict weather in finer and finer detail,” explained Schneider. The resolution of NOAA’s two global forecast models has improved from grids that are 24 kilometers, to ones that are about 13 kilometers.  “The finer you chop up the picture, the more you can see of what is happening inside a particular storm. This helps us make better forecasts.”

 “If we’re going to predict weather out beyond seven and 10 days, we need even better global weather forecast models that show us what’s occurring on the other side of the Earth,” added Schneider. “Weather patterns on one side of the globe travel around the Earth and evolve. Storms born in the western Pacific follow air patterns that can create major winter storms on the West Coast, and weather patterns off the coast of Africa can spawn hurricanes in the U.S.”

Source: NOAA

New research shows ocean warming poses "immediate threat" to keystone reef-building coral in the Caribbean

New research published in The Proceeding of the Royal Society - Biological Sciences provides new insights on the threat  ocean warming poses on coral growth in Mesoamerican barrier reefs.  The research, partially funded by CPO's Climate Monitoring program, used laboratory experiments to examine the adverse effects of ocean warming and acidification, and showed that the warming predicted by the IPCC for the end of the 21st century produced a five-fold decrease in coral calcification - the process by which corals produce calcium carbonate (CaCO3) and build reefs.

“The reef-building coral Siderastrea siderea exhibits parabolic responses to ocean acidification and warming,” is part of on-going work of NOAA-funded researcher Dr. Justin Ries that is looking at various aspects of climate variability, change, and ocean acidification on coral growth.  Dr. Ries and colleagues have been examining long term coral reef growth patterns at one of the largest barrier reefs in the world, off the coast of southern Belize. The research aims to create100 year records of coral growth at this reef by examining growth rates and environmental factors. As part of this work, Dr. Ries and his team found substantially decreasing growth rates over the last several years, at the same time that ocean acidification and temperature have been increasing.
Massive Starlet Coral (Siderastrea siderea) Image courtesy: D. Gordon E. Robertson via Creative Commons

This new research, led by post-doctoral researcher Dr. Karl Castillo, was designed to isolate the effects increasing ocean acidification and temperature had on Siderastrea sidereal, an important keystone and reef building coral species at the reef. By extracting coral colonies and returning them to the lab, researchers were able to design separate experiments around increasing temperature and decreasing ocean pH, and measure the coral response. While the most adverse effects on corals may arise from both acidification and temperature warming, researchers wanted to better understand the specific responses to these individually, which could aid efforts to predict and potentially mitigate the impacts of changing ocean conditions on coral.

They found that both ocean acidification and ocean warming had a “parabolic effect” on this important coral species. This means that while moderate decreases in the pH of seawater and moderate rises in temperature led to increases in coral building, in both cases researchers found a “tipping point” at which the coral calcification rates started decreasing. For ocean acidification, researchers recreated seawater conditions that would occur from the atmospheric carbon dioxide concentration from pre-industrial up through the present, the predicted end-of-century value, and up to six times the present condition. They found the “tipping point” at which calcification started leveling off and finally decreasing was actually well past the acidifications that would be expected by the end of century. For this particular species, they concluded, ocean acidification expected over the next century alone may not have a significant adverse effect.
Figure 1: Rates of reef-building calcification observed during the experiment for (left panel) increasing levels of ocean acidification and (right panel) temperatures ranging from 25C to 32C.

For warming ocean temperatures, however, the results were very different.  For the temperature experiments, researchers grew the coral colonies in temperatures from 25C to 32C, which covers the range of annual minimum and maximum temperatures of ocean temperatures recorded near the reef over 2002-2014, as well as annual average seawater temperatures expected over the next century. Thus the researchers were hoping to capture how the coral responds to the year to year variability seen now as well as what general conditions are predicted to by like by the end of the century. They found that while reef-building calcification rates increased for corals at 28C relative to 32C, skeletal building dropped off dramatically – nearly 80% - in corals growing at 32C. This parabolic response indicates that for this important reef building species, ocean warming over the next few decades could be an immediate serious threat, as conditions pass what the research found to be a species tipping point. Researchers note that the actual reef will experience changes in both stressors – ocean acidification and ocean warming – together over the next century, and will continue to work to understand how this and other reefs may respond.

You can watch a YouTube video on this and other aspects of Dr. Ries coral reef research here:  



Source: CRO

Pilot plant for removal of extreme gas charges from deep waters

Pit Lake Guadiana in the former mining area Herrerias in Andalusia, Spain.
Credit: : Bertram Boehrer/UFZ
Being part of the mining area Herrerias in Andalusia, deep waters of Pit Lake Guadiana show extremely high concentration of dissolved carbon dioxide (CO2). In the case of a spontaneous ebullition, human beings close-by would be jeopardized. To demonstrate the danger and the possible solution, scientists of the Spanish Institute of Geology and Mining, the University of the Basque Country (UPV/EHU, Bilbao) and the Helmholtz Centre for Environmental Research (UFZ) constructed a pilot plant for degassing. A fountain pulls deep water through a pipe to the surface, where the gas can escape from the water. The buoyancy produced by the bubbles provides the energy required for driving the flow.

"The deep water in the residual lake Guadiana contains an extremely high volume of carbon dioxide (CO2). Oxidation of ores has created a very acidic milieu, which is also known from other mining areas. In the mining area Herrerias however, this acidity dissolves carbonate from the rocks and produces carbonic acid (dissolved CO2), which can be accumulated under the high pressures of deep waters in the lake. There is not much circulation beyond 25 meter depth to remove the gas load" says Dr. Bertram Boehrer of UFZ, who is physicist and has been investigating stratification in lakes at many places on Earth. Due to the high hydrostatic pressure, each liter of deep water contains about 2.5 liters of CO2 gas. As long as the stratification remains stable, the gas is retained in the deep water. A land slide or other processes producing large water movements could facilitate a sudden release of gas previously confined under high pressure. Inhaled air of 8 percent CO2 are considered deadly for humans.

Now the scientists installed a degasing pipe which is the heart of the new pilot plant: Deep water enters a pipe at 61m depth. On the way up, hydrostatic pressure drops and gas bubbles form. The reduced density of the water-gas-mixture allows that deep water is pushed out of the pipe at the upper end to form a fountain above the water table, where gas is released to the atmosphere. This is an elegant solution, as the system does not require any additional driver, and the controlled release of CO2 does not pose any problem. "With this pilot plant, we could demonstrate that this approach also works in Guadiana pit lake. This can now be proposed to authorities as a possible approach to deal with the gas load." Though the lake in the mining area is fenced and access is not permitted to the public, this prohibition is difficult to survey.

Earlier installations in Lake Nyos in Cameroon served as a good example for this approach. In this lake, degassing pipes had been installed, which released the gas load with three fountains. On August 21st 1986, a large volume of gas escaped from the lake suddenly. The gas entered valleys of the surrounding area. 1700 human beings and thousands of animals were killed. The trigger could have been a land slide though this was never really proven. To avoid a repetition of this disaster, the gas load is slowly removed from the lake. One more crater lake called Monoun in Cameroon suffocated 37 human beings close to its shores in a similar eruption. Also in Monoun degasing fountains have been installed.

In Guadiana pit lake we do not see the same danger as in Lake Nyos, due to smaller size and depth. In addition, a density gradient between surface waters and deep waters is keeping the system stable. However, gas concentrations are so high that precaution must be taken. More detailed investigations must be implemented and remediation must be considered, says Dr. Boehrer. For the formation of such extreme gas loads, lakes must be sufficiently deep with incomplete winter recirculation (meromixis) and a strong carbon dioxide source. At the moment, we do not have such a lake in Germany.

Source: Helmholtz Centre for Environmental Research - UFZ

New insights into predicting future droughts in California: Natural cycles, sea surface temperatures found to be main drivers in ongoing event

Folsom Lake. Top photo taken in 2011, bottom taken in 2014.
Credit: CA Dept. of Water Resources
According to a new NOAA-sponsored study, natural oceanic and atmospheric patterns are the primary drivers behind California's ongoing drought. A high pressure ridge off the West Coast (typical of historic droughts) prevailed for three winters, blocking important wet season storms, with ocean surface temperature patterns making such a ridge much more likely. Typically, the winter season in California provides the state with a majority of its annual snow and rainfall that replenish water supplies for communities and ecosystems.

Further studies on these oceanic conditions and their effect on California's climate may lead to advances in drought early warning that can help water managers and major industries better prepare for lengthy dry spells in the future.
"It's important to note that California's drought, while extreme, is not an uncommon occurrence for the state. In fact, multi-year droughts appear regularly in the state's climate record, and it's a safe bet that a similar event will happen again. Thus, preparedness is key," said Richard Seager, report lead author and professor with Columbia University's Lamont Doherty Earth Observatory.
This report builds on earlier studies, published in September in the Bulletin of the American Meteorological Society, which found no conclusive evidence linking human-caused climate change and the California drought. The current study notes that the atmospheric ridge over the North Pacific, which has resulted in decreased rain and snowfall since 2011, is almost opposite to what models project to result from human-induced climate change. The report illustrates that mid-winter precipitation is actually projected to increase due to human-induced climate change over most of the state, though warming temperatures may sap much of those benefits for water resources overall, while only spring precipitation is projected to decrease.

The report makes clear that to provide improved drought forecasts for California, scientists will need to fully understand the links between sea surface temperature variations and winter precipitation over the state, discover how these ocean variations are generated, and better characterize their predictability.

This report contributes to a growing field of science-climate attribution-where teams of scientists aim to identify the sources of observed climate and weather patterns.

"There is immense value in examining the causes of this drought from multiple scientific viewpoints," said Marty Hoerling, report co-author and researcher with NOAA's Earth System Research Laboratory. "It's paramount that we use our collective ability to provide communities and businesses with the environmental intelligence they need to make decisions concerning water resources, which are becoming increasingly strained."

To view the report, visit: http://cpo.noaa.gov/MAPP/californiadroughtreport.

Source: National Oceanic and Atmospheric Administration

Another human footprint in the ocean: Rising anthropogenic nitrate levels in North Pacific Ocean

Hawaii Ocean Time-series Program scientists work aboard the R/V Ka'imikai-O-Kanaloa in the North Pacific Ocean. The HOT Program provided decades of data used to reconstruct historical nitrogen concentrations.
Credit: Paul Lethaby, UH SOEST
Human-induced changes to Earth's carbon cycle -- for example, rising atmospheric carbon dioxide and ocean acidification -- have been observed for decades. However, a study published this week in Science showed human activities, in particular industrial and agricultural processes, have also had significant impacts on the upper ocean nitrogen cycle.

The rate of deposition of reactive nitrogen (i.e., nitrogen oxides from fossil fuel burning and ammonia compounds from fertilizer use) from the atmosphere to the open ocean has more than doubled globally over the last 100 years. This anthropogenic addition of nitrogen has reached a magnitude comparable to about half of global ocean nitrogen fixation (the natural process by which atmospheric nitrogen gas becomes a useful nutrient for organisms). David Karl, Professor of Oceanography and Director of the Daniel K. Inouye Center for Microbial Oceanography at the University of Hawai'i, teamed up with researchers from Korea, Switzerland and the U.S. National Oceanic and Atmospheric Administration to assess changes in nitrate concentration between the 1960s and 2000s across the open North Pacific Ocean.

Their analysis, which could discern human-derived nitrogen from natural nitrogen fixation, revealed that the oceanic nitrate concentration increased significantly over the last 30 years in surface waters of the North Pacific due largely to the enhanced deposition of nitrogen from the atmosphere.

"This is a sobering result, one that I would not have predicted," said Karl. "The North Pacific is so vast it is hard to imagine that humans could impact the natural nitrogen cycle."
The researchers used ocean data in conjunction with the state-of-the-art Earth System Model to reconstruct the history of the oceanic nitrate concentration and make predictions about the future state of the North Pacific Ocean. Their assessment revealed a consistent picture of increasing nitrate concentrations, the magnitude and pattern of which can only be explained by the observed increase in atmospheric nitrogen deposition.

Enhanced nitrogen deposition has several potential ecological ramifications. Because biological activity is limited by nitrate availability in the North Pacific Ocean, the input of new nitrogen from the atmosphere may increase photosysnthesis in the sunlit layers and export of carbon-rich organic material out of the surface ocean into the deep.

"The burgeoning human population needs energy and food -- unfortunately, nitrogen pollution is an unintended consequence and not even the open ocean is immune from our daily industrial activities," said Karl.

Given the likelihood that the magnitude of atmospheric nitrogen deposition will continue to increase in the future, the North Pacific Ocean could rapidly switch to having surplus nitrate. Thus, past and future increases in atmospheric nitrogen deposition have the potential to alter the base of the marine food web; and, in the long term, the structure of the ecosystem.

In particular, the shift in nutrient availability could favor marine organisms that thrive under the high nitrate and low phosphorus conditions. If similar trends are confirmed in the Atlantic and Indian Oceans, it would constitute another example of a global-scale alteration of Earth system. Further, the findings of this study of the North Pacific highlight the need for greater controls on the emission of nitrogen compounds during combustion and agricultural processes.

Source: University of Hawaii at Manoa
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