Ocean Heating and Acidification: Difference between revisions
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=====Ocean Acidification's impact on oysters and other shellfish===== | |||
[https://www.pmel.noaa.gov/co2/story/Ocean+Acidification's+impact+on+oysters+and+other+shellfish?fbclid=IwAR1HSWMHRJFhQ_-7AWMqI0Wcv7NpM5O9RLX5hghOG1VUgX1GRuhtDqLShlI NOAA PMEL Carbon program 2019] | |||
HARI SREENIVASAN: But there's trouble in the water. The ocean's pH, which measures the level of acidity of a liquid, shows the water is becoming acidified. Most growers like the Wysockis can only farm oysters if they can buy oyster larvae, also called oyster seed, from hatcheries. But a few years ago, the larvae suddenly began dying by the billions. The culprit? The seawater pumped into the hatcheries is so corrosive that it eats away the young oyster shells before they can form. | |||
=====Acid oceans are shrinking plankton, fuelling faster climate change===== | =====Acid oceans are shrinking plankton, fuelling faster climate change===== | ||
[https://theconversation.com/acid-oceans-are-shrinking-plankton-fuelling-faster-climate-change-121443?fbclid=IwAR03GZuJv69LPKoyMq5cYR3ALPPgVcI3szM67RUv2uLoVXpoQtKFxCs7HJc The Conversation 8/26/19] | [https://theconversation.com/acid-oceans-are-shrinking-plankton-fuelling-faster-climate-change-121443?fbclid=IwAR03GZuJv69LPKoyMq5cYR3ALPPgVcI3szM67RUv2uLoVXpoQtKFxCs7HJc The Conversation 8/26/19] | ||
Revision as of 09:14, 27 August 2019
Ocean Acidification's impact on oysters and other shellfish
HARI SREENIVASAN: But there's trouble in the water. The ocean's pH, which measures the level of acidity of a liquid, shows the water is becoming acidified. Most growers like the Wysockis can only farm oysters if they can buy oyster larvae, also called oyster seed, from hatcheries. But a few years ago, the larvae suddenly began dying by the billions. The culprit? The seawater pumped into the hatcheries is so corrosive that it eats away the young oyster shells before they can form.
Acid oceans are shrinking plankton, fuelling faster climate change
In our study we discovered increased seawater acidity reduced Antarctic phytoplanktons’ ability to build strong cell walls, making them smaller and less effective at storing carbon. At current rates of seawater acidification, we could see this effect before the end of the century.
Global alteration of ocean ecosystem functioning due to increasing human CO2 emissions
Ocean warming and acidification have received increasing focus as global change stressors, but marine species will also be impacted in their performance by other emerging stressors such as changes in sea surface height, UV, underwater irradiance, water salinity, and seawater oxygen content (7). Hypoxic zones are becoming widespread in oceanic as well as shelf environments because of climate change and local stressors such as eutrophication (37). Many species will be challenged by the interactive effects of ocean warming, acidification, and deoxygenation, but at present, hardly any (multistressors) studies exist to evaluate the effects of hypoxia on marine species and ecosystems (8, 38). For some species, there are opportunities to move to deeper waters or extend their ranges to higher latitudes, but not all species will be able to keep up with the pace of climate change, leading to alterations in current species distributions (39, 40). Moreover, species that have fewer generations (e.g., k strategists with greater longevity and later maturation) have fewer opportunities to adapt to rapidly changing conditions forecast for the next ∼85 y. Unless longer-lived species relocate to climate refugia
A study of 632 published experiments of the world’s oceans, from tropical to arctic waters, spanning coral reefs and the open seas, found that climate change is whittling away the diversity and abundance of marine species. The paper, published in the Proceedings of the National Academy of Sciences, found there was “limited scope” for animals to deal with warming waters and acidification, with very few species escaping the negative impact of increasing carbon dioxide dissolution in the oceans.
Phytoplankton Population Drops 40 Percent Since 1950
Researchers at Canada's Dalhousie University say the global population of phytoplankton has fallen about 40 percent since 1950. That translates to an annual drop of about 1 percent of the average plankton population between 1899 and 2008. The scientists believe that rising sea surface temperatures are to blame. "It's very disturbing to think about the potential implications of a century-long decline of the base of the food chain," said lead author Daniel Boyce, a marine ecologist.
Critical Ocean Organisms Are Disappearing
he number of marine phytoplankton, the microscopic organisms that gobble greenhouse gases and directly or indirectly feed every animal in the ocean, has been declining by about 1% of the global average per year, according to a new study. If the trend continues, it could decimate ocean food chains and accelerate global warming.
Icebergs delay Southern Hemisphere future warming, study shows
Future warming can accelerate the disintegration of the West Antarctic ice sheet. A large fraction of the ice will enter the Southern Ocean in form of icebergs, which melt and provide a cooling and freshening effect to the warmer and denser ocean water. This process will increase the formation of sea-ice and shift winds and ocean currents. The overall effect is a slowdown in the magnitude of human-induced Southern Hemispheric warming and sea-level rise, according to a new study.
Pacific Ocean's effect on Arctic warming
The Arctic is experiencing larger and more rapid increases in temperature from global warming more than any other region, with sea-ice declining faster than predicted. This effect, known as Arctic amplification, is a well-established response that involves many positive feedback mechanisms in polar regions. Q7 What has not been well understood is how sea-surface temperature patterns and oceanic heat flow from Earth's different regions, including the temperate latitudes, affect these polar feedbacks. This new research suggests that the importance of changes occurring in the Pacific may have a stronger impact on Arctic climate than previously recognized.
Marine heatwaves kill coral instantly
Increasingly frequent marine heatwaves can lead to the almost instant death of corals, scientists working on the Great Barrier Reef have found. Scientists studying coral after a heat event discovered that extreme temperature rises decayed reefs much more rapidly than previously thought.
Rapid Coral Decay Is Associated with Marine Heatwave Mortality Events on Reefs
Severe marine heatwaves have recently become a common feature of global ocean conditions due to a rapidly changing climate [1, 2]. These increasingly severe thermal conditions are causing an unprecedented increase in the frequency and severity of mortality events in marine ecosystems, including on coral reefs [3]. The degradation of coral reefs will result in the collapse of ecosystem services that sustain over half a billion people globally [4, 5]. Here, we show that marine heatwave events on coral reefs are biologically distinct to how coral bleaching has been understood to date, in that heatwave conditions result in an immediate heat-induced mortality of the coral colony, rapid coral skeletal dissolution, and the loss of the three-dimensional reef structure.
Heatwaves 'cook' Great Barrier Reef corals
In surveying the 3,863 individual reefs that make up the system off Australia's north-east coast, scientists found that 29% of communities were affected. In some cases up to 90% of coral died, in a process known as bleaching.
This occurs when the stress of elevated temperatures causes a breakdown of the coral's symbiotic relationship with its algae, which provide the coral with energy to survive, and give the reef its distinctive colours.
Coral reefs head for 'knock-out punch'
A study of 100 reefs, published in Science Magazine, shows the interval between bleaching events in recent decades has shortened dramatically. It has gone from once every 25-30 years in the early 1980s to an average of just once every six years today.Bleaching is caused by anomalously warm water, which prompts coral polyps to eject their symbiotic algae.This drains the corals of their colour and is fatal unless conditions are reversed in a reasonably short time. But even if temperatures fall back quickly, it can still take many years for damaged reefs to fully recover.
Record Warm Water Likely Gave Kuskokwim Salmon Heart Attacks
Earlier this week, water temperatures near Bethel broke into the lower 70s, marking the highest river temperature that’s ever been recorded in early July. This spell was part of a heat wave that shot thermometers to their highest point ever in towns across Alaska. During this time, residents along the lower Kuskokwim River from Tuntutuliak to Akiak reported dead salmon floating downstream. Salmon don’t function well past 70 degrees, and the water had pushed just above that limit.
Climate Change is Weakening an Ocean Current
Both studies found that melting ice from Greenland has spilled huge quantities of freshwater into the North Atlantic, diluting the dense salinity of North Atlantic currents and weakening the AMOC by 15 percent. However, the results disagree on when the changes started. For decades, scientists have worried that human-caused global warming could weaken this system and drastically alter weather patterns. It’s an idea best known from the scientifically and cinematically awful 2004 film The Day After Tomorrow.
Heatwaves sweeping oceans ‘like wildfires’, scientists reveal
Ocean Heat Waves The Guardian 2019
The number of heatwaves affecting the planet’s oceans has increased sharply, scientists have revealed, killing swathes of sea-life like “wildfires that take out huge areas of forest”. The damage caused in these hotspots is also harmful for humanity, which relies on the oceans for oxygen, food, storm protection and the removal of climate-warming carbon dioxide the atmosphere, they say.
Ocean acidification is already harming the Great Barrier Reef’s growth
It was clear from our results that reef calcification was around 7% higher under pre-industrial conditions than those experienced today. Our work provides the first strong evidence from experiments on a natural ecosystem that ocean acidification is already causing reefs to grow more slowly than they did 100 years ago. Ocean acidification is already taking its toll on coral reef communities. This is no longer a fear for the future; it is the reality of today.
