A truly amazing sight is the arrival of a billion indian oil sardines, amassing to over three miles long they can confuse their predators but one of them is unavoidable...
Taken from Wild Arabia
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Saturday, July 4, 2015
Friday, July 3, 2015
Oceans face massive and irreversible impacts without carbon cuts – study
The risks currently being experienced across the planet.
Most, if not all, are set to increase.
Regional changes in the physical system and associated risks for natural and human-managed systems.
Source: Science; Gattuso et al. (2015) modified from IPCC WGII AR5 (2014).
From The Guardian I / II
Business-as-usual carbon emissions would cause global warming that brings serious ocean acidification, death of corals and mangroves, scientists say
Time is rapidly running out for the world’s oceans and the creatures that live in them as the Earth’s climate continues to warm, say scientists.
Only “immediate and substantial” reductions in greenhouse gas emissions can hope to prevent “massive” impacts on marine ecosystems, warn the experts.
Researchers compared the fate of the oceans under two scenarios, one a “business-as-usual” approach and the other involving drastic cuts in emissions.
Their analysis showed that business-as-usual would have an enormous and “effectively irreversible” impact on ocean ecosystems and the services they provide, such as fisheries, by 2100.
Only “immediate and substantial” reductions in greenhouse gas emissions can hope to prevent “massive” impacts on marine ecosystems, warn the experts.
Researchers compared the fate of the oceans under two scenarios, one a “business-as-usual” approach and the other involving drastic cuts in emissions.
Their analysis showed that business-as-usual would have an enormous and “effectively irreversible” impact on ocean ecosystems and the services they provide, such as fisheries, by 2100.
Even after curbing emissions of carbon dioxide (CO2) enough to prevent temperatures rising by more than 2C compared with pre-industrial levels, many marine ecosystems would still suffer significantly, they said.
The international team led by Dr Jean-Pierre Gattuso, from the Laboratoire d’Océanographie de Villefranche in France, wrote in the journal Science: “Impacts on key marine and coastal organisms, ecosystems, and services from anthropogenic (man-made) CO2 emissions are already detectable, and several will face high risk of impacts well before 2100, even with the stringent CO2 emissions scenario.
“These impacts are occurring across all latitudes and have become a global concern that spans the traditional north/south divide.”
Any new global climate agreement that fails to minimise the impact on oceans will be “incomplete and inadequate”, stressed the scientists.
The international team led by Dr Jean-Pierre Gattuso, from the Laboratoire d’Océanographie de Villefranche in France, wrote in the journal Science: “Impacts on key marine and coastal organisms, ecosystems, and services from anthropogenic (man-made) CO2 emissions are already detectable, and several will face high risk of impacts well before 2100, even with the stringent CO2 emissions scenario.
“These impacts are occurring across all latitudes and have become a global concern that spans the traditional north/south divide.”
Any new global climate agreement that fails to minimise the impact on oceans will be “incomplete and inadequate”, stressed the scientists.
Changes in ocean physics and chemistry and impacts on organisms and ecosystem services according to stringent (RCP2.6) and high business-as-usual (RCP8.5) CO2 emissions scenarios.
The findings are intended to inform the forthcoming 2015 United Nations climate change conference in Paris.
By 2050, the loss of critical habitats such as coral reefs and mangroves was expected to contribute to “substantial declines” for tropical fisheries, on which many human communities depended, said the researchers.
This was the case even under the 2C emission cutting scenario.
While Arctic fisheries may benefit from warmer temperatures at first, the scientists pointed out that this region was a “hot spot” of ocean acidification.
While Arctic fisheries may benefit from warmer temperatures at first, the scientists pointed out that this region was a “hot spot” of ocean acidification.
It also contained communities that were highly reliant on the sea.
Acidification, warmer oceans, sea level rise threaten the all marine ecosystems...in that video, the Ocean Initiative 2015 Project provides straightforward answers to this issue.
A new paper just published in Science summarizes the projected impacts of climate change on the world’s oceans, and consequently on humans and our economy.
The study concludes that global warming beyond the international limit of 2°C above pre-industrial temperatures would pose serious threats to marine ecosystems and their millions of human dependents.
It builds on the consensus science published by the Intergovernmental Panel on Climate Change last year.
The study concludes,
Ocean changes associated with a 2°C warming of global surface temperature carries high risks of impacts and should not be exceeded.
Ocean changes associated with a 2°C warming of global surface temperature carries high risks of impacts and should not be exceeded.
The oceans have absorbed over 90% of the excess heat and 28% of the carbon pollution generated by human consumption of fossil fuels.
As the authors of the paper note, in many regions, the ocean plays an important role in the livelihood and food supply of human populations.
The ocean represents more than 90% of the Earth’s habitable space, hosts 25% of eukaryotic species, provides 11% of global animal protein consumed by humans, protects coastlines, and more.
‘Irreversible change’ to sea life from CO2
A major report warns that life in the seas will be irreversibly changed unless CO2 emissions from industrial society are drastically cut.
Twenty-two experts in the journal Science say the oceans are heating, losing oxygen and becoming more acidic - all in response to our carbon dioxide.
The scientists in Germany have been studying an event five million years ago that could throw light on today's challenges.
A major report warns that life in the seas will be irreversibly changed unless CO2 emissions from industrial society are drastically cut.
Twenty-two experts in the journal Science say the oceans are heating, losing oxygen and becoming more acidic - all in response to our carbon dioxide.
The scientists in Germany have been studying an event five million years ago that could throw light on today's challenges.
The study considers human impacts on the world’s oceans under two different scenarios.
The first is a business-as-usual high fossil fuel consumption scenario (called RCP8.5 in the latest IPCC report), and the second is a scenario in which humans take immediate serious steps to curb fossil fuel consumption (called RCP2.6).
Between now and 2100, RCP8.5 involves 6 times more global carbon pollution emitted by humans than RCP2.6.
The societal effort involved in reducing fossil fuel consumption and carbon emissions to meet RCP2.6 is obviously much greater than the effort involved in the do-nothing scenario, but this study finds that the outcomes are also starkly different for the world’s oceans.
The societal effort involved in reducing fossil fuel consumption and carbon emissions to meet RCP2.6 is obviously much greater than the effort involved in the do-nothing scenario, but this study finds that the outcomes are also starkly different for the world’s oceans.
In the business-as-usual scenario, by 2100 the oceans would be about 30 cm higher, oxygen content nearly 2% lower, ocean acidity 70% higher, and sea surface temperatures about 2°C hotter than in RCP2.6.
The authors write,
In summary, the carbon that we emit today will change the Earth System irreversibly for many generations to come. The ocean’s content of carbon, acidity, and heat as well as sea level will continue to increase long after atmospheric CO2 is stabilized. These irreversible changes increase with increasing emissions, underscoring the urgency of near-term carbon emission reduction if ocean warming and acidification are to be kept at moderate levels.
"Oceans - The sinks of our World": gives an example of how public engagement can make a significant contribution to scientific investigations of the effects of global warming and ocean acidification on marine life.
The film introduces us to a man who has been recording the temperature of the sea in his region of the Mediterranean Sea for forty years.
Now he is also collecting water samples to support scientific investigations on ocean acidification.
His work is of great importance to scientists who are studying the impacts of increasing emission of CO2, driven by human fossil fuel combustion, on the temperature and chemical make- up of our oceans.
Questions about the impact ocean acidification may have already caused to the health and diversity of marine life need to be answered.
However, questions about how the conditions for marine organisms may change in the future also matter greatly.
After all, experimental research in the laboratory and observations of marine life close to undersea volcanic vents have already shown that that calcifying organisms, such as chorals, are greatly affected by an increase of acidity in the water.
The film invites the viewer to observe scientific investigations in the laboratory but more so to join scientists as they conduct their investigations at under water sites.
(EUSEM)
As an example of one consequence of these changes, many marine species are shifting to different geographic regions as the oceans warm.
These shifts can pose serious challenges for fisheries.
Recent studies strongly reiterate that many species—including various invertebrates, commercially important fish species and marine mammals—are undergoing phenological and geographical shifts of up to 400 km per decade as a result of warming.
Recent studies strongly reiterate that many species—including various invertebrates, commercially important fish species and marine mammals—are undergoing phenological and geographical shifts of up to 400 km per decade as a result of warming.
These geographical species shifts are projected to occur about 65% faster in the business-as-usual scenario than under RCP2.6.
Coral reefs are particularly sensitive to human-caused ocean changes.
Coral reefs are particularly sensitive to human-caused ocean changes.
They provide habitat for almost a quarter of the species in the oceans.
Hundreds of millions of people rely on the coastal protection, tourism, and food provided by coral reef ecosystems.
However, the authors of this study note that the dual threats of global warming and ocean acidification pose a serious threat to coral reefs.
Reef-building corals are extremely vulnerable to warming.
Warming causes mass mortality of warm-water corals through bleaching as well as through biotic diseases, resulting in declines in coral abundance and biodiversity.
Coral reefs can recover from bleaching events when thermal stress is minimal and of short duration.
However, ocean warming and acidification are expected to act synergistically to push corals and coral reefs into conditions that are unfavorable for coral reef ecosystems.
There is limited agreement and low confidence on the potential for corals to adapt to rapid warming.
The study also estimates some of the economic impacts of ocean changes in the business-as-usual scenario.
For example, lost coastal habitats and sea level rise could combine to expose 0.2 to 4.6% of the global population to inundation annually at a cost of 0.3 to 9.3% to global GDP.
In terms of tourism dollars, the difference between the two scenarios amounts to about $10 billion per year, hitting Australia and the USA particularly hard.
Loss of coral reefs to tourism under the RCP2.6 and RCP8.5 scenarios could cost between US$1.9 billion and US$12 billion per year, respectively.
In terms of tourism dollars, the difference between the two scenarios amounts to about $10 billion per year, hitting Australia and the USA particularly hard.
Loss of coral reefs to tourism under the RCP2.6 and RCP8.5 scenarios could cost between US$1.9 billion and US$12 billion per year, respectively.
Coral reef losses due to ocean warming and acidification on the Great Barrier Reef place up to $5.7 billion and 69,000 jobs in Australia at risk.
In addition, ocean acidification may cause an annual loss of reef ecosystem services that are valued up to US$1 trillion by 2100.
For about a quarter of countries with reef-related tourism, mainly less developed countries, this kind of tourism accounts for more than 15% of gross domestic product and is more sustainable than extractive livelihoods.
The study also makes a critical and often-overlooked point.
The study also makes a critical and often-overlooked point.
Some people believe geoengineering is a better or more practical solution than curbing our carbon pollution.
Geoengineering proposals often involve slowing global warming by reducing the amount of sunlight absorbed by the Earth, for example by pumping sulfur high into the atmosphere, or putting large mirrors into orbit.
However, these proposals wouldn’t curb human carbon emissions, and hence wouldn’t slow the accumulation of carbon in the oceans, or the resulting ocean acidification.
Ultimately, the authors warn that immediate action to cut carbon pollution is critical if we want to curb the rapid and dangerous impacts already being observed in the world’s oceans.
…immediate and substantial reduction of CO2 emissions is required in order to prevent the massive and effectively irreversible impacts on ocean ecosystems and their services that are projected with emissions scenarios more severe than RCP2.6. Limiting emissions to below this level is necessary to meet UNFCCC’s stated objectives. Policy options that overlook CO2, such as solar radiation management and control of methane emission, will only minimize impacts of ocean warming and not those of ocean acidification.
Links :
Ultimately, the authors warn that immediate action to cut carbon pollution is critical if we want to curb the rapid and dangerous impacts already being observed in the world’s oceans.
…immediate and substantial reduction of CO2 emissions is required in order to prevent the massive and effectively irreversible impacts on ocean ecosystems and their services that are projected with emissions scenarios more severe than RCP2.6. Limiting emissions to below this level is necessary to meet UNFCCC’s stated objectives. Policy options that overlook CO2, such as solar radiation management and control of methane emission, will only minimize impacts of ocean warming and not those of ocean acidification.
Links :
- BBC : CO2 emissions threaten ocean crisis
Thursday, July 2, 2015
Oceans could be headed for marine industrial revolution
A map of United States marine protected areas.(Photo Credit: NOAA)
From Sea Technology
History repeats itself, and according to a new report, the same patterns that affected species extinction on land could be happening in the global oceans.
Despite this trend, however, we can help shape the future of ocean life by advocating for more marine protected areas and being an informed consumer.
Sea Technology spoke with Douglas McCauley, a University of California, Santa Barbara scientist who worked on the report, about what terrestrial species extinction means for marine life and the industrialization of the oceans.
Marine defaunation: Animal loss in the global ocean
How many land-based species have gone extinct?
In the last 500 years, there have been about 500 species of terrestrial animals that have gone extinct. There are many more that have gone extinct prior to 500 years, but some of the record keeping gets harder to do when you move back thousands of years.
What we are trying to do is focus on extinctions that are driven by people.
It's easier to concentrate on the past five centuries, where we know much more about what has happened to the environment.
In the ocean, in the same time period, 15 animals have been lost.
Why is the trend of species extinction on land important when looking at marine life?
It is a way for us to get a sense of how history can inform the future.
Things are basically behind in the oceans, in terms of our impact on wildlife communities, relative to our impacts on land.
It seems that we run through a couple of different transitions in the way that we influence wildlife.
When we look back at what happened on land, we can see how these transitions took form and what the consequences were.
We started hunting animals directly.
Then, we switched over to using the resources and space that animals use, hunting their homes and degrading their habitats.
That transition toward moving from hunting directly to hunting the land they use happened about the time, in a serious way, of the Industrial Revolution.
It was during that period where we were degrading habitats more rapidly that we also saw a major elevation in rates of terrestrial animal extinction.
In the oceans, the clock is turned back.
We're still hunting animals directly.
What we report is that there may be early signs of going toward this same shift in the ocean.
If we look at a wide range of data sources from marine industry, it seems there is a lot of new growth in development in the oceans.
We are now beginning to use space in the oceans at unprecedented rates.
That may be pushing us toward a period where we begin to industrialize our use of space in the oceans.
You mention a marine industrial revolution.
Is this shift what that refers to?
Exactly.
The terrestrial Industrial Revolution was about building out our cities and factories and using resources from wild spaces.
That seems to be what we are seeing early signs of in the ocean.
We are building power plants in the oceans.
We're beginning to set ourselves up to start mining in the oceans.
There are more than 1 million square kilometers of seabed that have been set aside for future mining. We're beginning to farm in an almost industrial-strength way.
It seems like some of the signs in these data remind us of the early days of the terrestrial Industrial Revolution.
As an ecologist, that's where we get a bit worried, because we saw this explosion of growth go hand-in-hand with major extinction rates.
We don’t want that to happen in the oceans.
We need to be careful about where we put this industry and what rates we let it develop.
In your research, how do you correlate human actions and species extinction?
The nice thing is, with only 15 animal extinctions in the oceans, there is not a lot of ambiguity.
You take an animal like the Caribbean monk seal, one of the more charismatic marine animals that was driven extinct.
It was just hunting.
We can look at historical records.
We arrive, and we start directly hunting the seals.
Future extinctions get a bit more complicated.
The major shift is that climate change is going to be a challenge in the oceans.
We are making the oceans more acidic and warmer, and that's a new source of stress that these animals have to cope with.
So, if their populations are getting low, they have to work though the process of adaption to a new environment.
So much of the ocean is unexplored. How does that play into your research?
The oceans are incredibly difficult places to study and understand.
This is the reason why a report like this is new.
We have been talking about these extinctions that are taking place on land, and the science is so much easier to document on land.
Doing it in the ocean is a lot harder.
First of all, this report is coming out a little late because of the challenges describing these patterns of change in the ocean.
They can only be incomplete views.
This is the best distillation of information from so many different sources, yet it remains a pretty incomplete view of what's happening out there with marine wildlife.
What can we do to help preserve marine species?
There are some big things and some small things.
Put more parks in the ocean.
Everybody knows that protected areas, parks on land, are the places you go to see wildlife.
Marine wildlife also thrives in parks.
We have far fewer protected areas in the oceans than we have on land.
We simply need more.
We need to address climate change.
It doesn't help us to set aside space for wildlife if we are heating up that space and acidifying it.
You don't think about a connection between what kind of miles-per-hour rating your car gets and oysters or tropical fish, but there is in fact a connection.
Everything that we do in our daily lives to reduce carbon emissions is going to buy marine animals time.
Use less plastic.
There are five trillion pieces of plastic in the oceans.
The last thing I'd say is don't eat endangered wildlife.
Use one of the smartphone applications to sort through your seafood section to figure out which are the rhinos of the sea.
Links :
- NYTimes : Ocean Life Faces Mass Extinction, Broad Study Says
Wednesday, July 1, 2015
Europe is set to get colder: Melting sea ice could weaken the Gulf Stream and cause temperatures to plummet
The Gulf stream and climate change
The global conveyer belt is part of the large-scale ocean circulation that is driven by differences in the density of the waters.
It plays a key role in keeping the climate at balance and Europe warm.
Global warming may change it forever with unforeseeable consequences.
- Researchers studied winter weather data from between 1958 and 2014
- They found ice in Iceland and Greenland seas has reduced in past 30 years
- As sea ice retreats, air-heat exchanges that regulate climate are affected
- And this could leading to colder temperatures along the Western Europe
- Scientists have not specified how much temperatures could be affected
As climate change warms enormous portions of Earth, melting sea ice may actually cause Europe to become colder, a study has claimed.
Over the past 30 years, ice levels in the Icelandic and Greenland seas - regions key to regulating Earth's climate system - have significantly reduced.
Scientists believe that in turn this loss of ice will cause the flow of warmer water from the tropics to be affected, weakening the Gulf Stream and leading to cooler temperatures in Western Europe.
Over the past 30 years, ice in the Iceland and Greenland seas has significantly reduced (1900 to 1909 shown at (a), 1930 to 1939 (b), 1960 to 1969 (c) and 2000 to 2009 (d).) By reducing the size of these regions, the warmer water that travels up from the tropics is affected, leading to colder temperatures along western Europe
'A warm western Europe requires a cold North Atlantic Ocean, and the warming that the North Atlantic is now experiencing has the potential to result in a cooling over Western Europe,' said lead researcher Professor Kent Moore from University of Toronto Mississauga (UTM)'s Department of Chemical and Physical Sciences.Experts claim the disappearance of Arctic sea ice will lead to a reduction in cold, dense water - generated through a process known as oceanic convection - which flows south and feeds the Gulf Stream.
If this convection decreases, the Gulf Stream may weaken, thereby reducing the warming of the atmosphere.
The research, published in Nature Climate Change, is the first attempt to examine how changes in the air-sea heat exchange in the region are brought about by global warming.
The research also marks the first time researchers have considered its possible impact on oceanic circulation, including the Atlantic Meridional Overturning Circulation (Amoc).
The Atlantic Meridional Overturning Circulation (Amoc) is a major current in the Atlantic Ocean.
A flow of warm, salty water travels north in the upper layers of the Atlantic, while a colder flow of water moves south in the deep Atlantic.
Given its size and location on the planet, Amoc plays an important role in maintaining and controlling the Earth's climate system.
The "cloud streets" over the Greenland and Iceland seas shown in this satellite image exist as a result of heat and moisture transfer processes that warm the atmosphere and cool the ocean
(NASA)
(NASA)
This heat is then transferred to the atmosphere and moderates the climate in this region.
As the heat is transferred, the water becomes colder and more dense and this sinks and travels back to the south and eventually rises again in the tropics.
This transfer of heat - known as an air-sea heat exchange - occurs in the Iceland and Greenland seas where the conditions are ideal for this convection to happen.
In particular, they each contain gyres that are shaped in such a way that make it easier for the hot water to rise and the cold water to sink in such a substantial way.
As the sea ice decreases, the distance between these two gyres and edge of the ice becomes wider and reduces the maximum region where the heat exchange can take place.
By studying data from between 1958 and 2014 taken from the European Centre for Medium-Range Weather Forecasts and model simulations, the researchers noticed this region is already 20 per cent smaller than 30 years ago.
As global warming heats the Earth and ocean, the retreat of the sea ice means there won't be as much cold, dense water, generated through oceanic convection (illustrated), created to flow south and feed the Gulf Stream. If convection decreases, the Gulf Stream may weaken and reduce the warming of the atmosphere
And if this decrease continues, they say it will weaken the overturning loop that feeds the North Icelandic Jet, thus reducing the supply of the densest water to the Amoc.
'The heat exchange is weaker - it's like turning the stove down 20 per cent,' continued Professor Moore. 'We believe the weakening will continue and eventually cause changes in the Atlantic Meridional Overturning Circulation and the Gulf Stream, which can impact the climate of Europe.'
The paper's other authors are Kjetil Vǻge from the University of Bergen, Robert Pickart from Woods Hole Oceanographic Institution and Ian Renfrew from the University of East Anglia.
Links :
- WashingtonPost : Melting Arctic sea ice could be disrupting the oceans circulation with potentially major consequences
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