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New Report: ‘Blowtorch’-Like Ocean Warming Advances Killer Seas, Shifts El Nino, Heats Hydrates

Tampering can be dangerous. Nature can be vengeful. We should have a great deal of respect for the planet on which we live. — Carl-Gustaf Rossby

But as the [IUCN] study points out, 90% of the extra heat that our greenhouse gases trap is actually absorbed by the oceans. That means that the upper few meters of the sea have been steadily warming more than a tenth of a degree celsius per decade, a figure that’s accelerating. When you think of the volume of water that represents, and then try to imagine the energy necessary to raise its temperature, you get an idea of the blowtorch that our civilization has become. — Bill McKibben

The scale of ocean warming is truly staggering with the numbers so large that it is difficult for most people to comprehend. — from the IUCN report Explaining Ocean Warming: Causes, scale, effects and consequences

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If there’s one simple fact about past Earth climates that should keep you awake at night, it’s this — warming the world ocean eventually produces a killing mechanism that is unrivaled by any other in Earth’s deep past. Great asteroids, gamma-ray bursters, earthquakes, tsunamis and volcanism — none of these can rival the vast damage to life on planet Earth that is resulting from ocean warming.

As a study of the sciences, this assertion would be merely an academic one if the human race weren’t now involved in a great injection of an unprecedented volume of greenhouse gasses into the Earth’s airs. As a critical new ocean report from the International Union for Conservation of Nature (IUCN) points out, these gasses are trapping an extraordinary amount of heat at the top of the world’s atmosphere. In turn, the atmosphere is transferring the lion’s share of this heat — more than 90 percent — into the waters of our world.

The Extreme Amount of Heat Energy Piling up in Our Warming Ocean

As a result, the surface of the world ocean is warming by 0.1 degree Celsius per decade. That may not sound like much, but it takes about four times the amount of energy to warm one gram of water by 0.1 C as it does one gram of air. This property, called specific heat, is a defining aspect of water. Water has the highest specific heat of any common substance.

heat-accumulation-human-forced-zillions-of-joules

(Since the 1970s, about 300 zettajoules’ (ZJ) worth of heat energy has accumulated in the Earth System due to fossil-fuel burning and related greenhouse gas emissions. That’s about 5 Hiroshima bombs worth of heat accumulating every second. Most of that energy has gone into the world’s oceans. So much heat is bound to have consequences, and these impacts are starting to show up in the form of declining ocean health, melting sea ice and glaciers, shifting climate zones and weather patterns, worsening droughts and storms, and threats of Earth System carbon feedbacks. Image source: Explaining Ocean Warming.)

Liquid water is also far denser than air. And this density generates an even higher impact heat energy transfer multiplier. So not only does it take four times more energy to warm a similar weight of water vs air, once warmed, that water contains that higher level of specific heat energy in a much more tightly concentrated package. And when that high heat concentration liquid water comes into contact with other substances — like ice in the form of ocean contact, or air in the form of evaporation, or frozen hydrates on the sea bed — it can pack a serious heat punch.

The vast volume of water in our oceans, therefore, serves as a kind of heat and energy regulator. It takes a lot of energy to warm it up, but once it does, serious environmental changes start to happen as a result. In other words, the temperature of the global ocean could be viewed as the point on which the whole of the Earth climate system pivots. Once the oceans are set in thermal motion, serious changes to the rest of the world are going to take place. To get an idea how much energy the oceans now contain, of how much potential they now have to dramatically alter our world, consider that if these vast waters were not present, the atmosphere now would have already warmed by 36 degrees C due to the heat-trapping effect of greenhouse gasses already in our atmosphere.

Fossil-fuel blowtorch indeed.

Heating Seas Ultimately Become Killer Seas

There’s a starker message to convey here, one that focuses on this simple yet dire question — how do warming oceans kill? In basic terms, they become toxic and anoxic. Warming oceans melt ocean-contacting glaciers. The glacial melt forces seas to rise and forms a freshwater lid on the global ocean, breaking down ocean conveyor belts and preventing mixing. This freshwater lid also deflects heat toward the ocean bottom. This process in turn helps to thaw methane hydrates. Warm waters that don’t mix and that are filled with bubbling hydrates become very oxygen-poor.

barents-algae-bloom

(Massive algae bloom covers tens of thousands of square miles of open water in the Barents Sea during August of 2016. As glaciers melt, oceans stratify and warm; as water oxygen levels drop, and as hydrates vent due to warming, such blooms result in significant reductions to ocean health and a related global mass-extinction threat. Image source: LANCE MODIS.)

As the land glaciers bleed out into the oceans, the stratified, oxygen-deprived waters become less and less able to support advanced life. The kinds of life warm, oxygen-deprived waters do support are poison-producing microbes. These microbes thrive in the warm, oxygen-poor waters. If ocean heating continues to progress, the warming seas will eventually fill up with their deadly byproducts. Among the most nasty of these is hydrogen sulfide. If enough of it is produced, it will spill out from the ocean into the nearby air, resulting in land animal mortality as well.

In microcosm, we saw a mild taste of some of these effects this past year in Florida as toxic algae blooms filled the warming state’s waterways and coastlines, even forcing some riverside marinas to close due to toxic gasses wafting up from the purple-green, oxygen-starved waters. These effects are a snapshot of a possible future for Earth’s oceans if we don’t get our act together yesterday.

El Niño Shifted, Ocean Hydrates Threatened

As alluded to earlier in this post, a new report, Explaining Ocean Warming, provides some pretty hard evidence that the oceans are on the move toward a much more harmful global climate state. The study, which has rightly received a great deal of media attention, issues a ‘shot across the bow’ warning to pretty much everyone living today. And it finds serious impacts to the ocean and linked climate systems due to a very rapid human-forced global warming.

These hard findings are worth reading directly:

  1. Sea-surface temperature, ocean heat content, sea-level rise, melting of glaciers and ice sheets, CO2 emissions and atmospheric concentrations are increasing at an accelerating rate with significant consequences for humanity and the marine species and ecosystems of the ocean.
  2. There is likely to be an increase in mean global ocean temperature of 1-4 degrees C by 2100. The greatest ocean warming overall is occurring in the Southern Hemisphere and is contributing to the subsurface melting of Antarctic ice shelves. Since the 1990s the atmosphere in the polar regions has been warming at about twice the average rate of global warming.
  3. There is likely to be Arctic warming and ice loss, and possibly the essential removal, in some years, of the summer Arctic sea ice within the next few decades.
  4. Over the last 20 years there has been an intensification and distinct change in the El Niño events, with a shift of the mean location of sea-surface temperature anomalies towards the central Pacific.
  5. Currently 2.5 Gt of frozen methane hydrate are stored in the sea floor at water depths of 200 to 2000 m. Increasing water temperature could release this source of carbon into the ocean and ultimately into the atmosphere.

These are all Earth-shattering scientific statements. For those who frequent this blog, points 1 through 3 are probably pretty familiar. The last two, however, require more in-depth explanation.

global-warming-el-nino

(Some scientific studies have pointed out that warming the world ocean will result in a shift of El Niño toward the central Pacific. A new ocean report finds that it’s already happening. Image source: Global Warming May Dent El Niño’s Protective Hurricane Shield, Increase Droughts.)

For a long time now, scientists have believed that El Niño wouldn’t be affected by climate change until the end of this century. But as with sea ice, it appears that such impacts may well be advancing faster than expected. As we’ve alluded to here, there’s been an apparent shift in El Niño toward the central Pacific over recent decades. This may well be a climate change-related shift. The fact that the IUCN report highlights this change is a sign that the broader sciences are starting to tackle the notion of early alterations to El Niño due to climate change as well.

However, the most ominous language here centers around methane hydrate. For years, there’s been adamant push-back against potential risks to hydrates coming from well-respected sections of the climate sciences. Nonetheless, those downplaying the threat of warming to hydrates have yet to produce any conclusive proof as to why warming the ocean bottom and applying heat to hydrates won’t result in at least some feedback from these carbon stores (especially under the higher-range warming scenarios). The IUCN report reiterates this risk by identifying 2.5 billion tons of frozen seabed methane at shallow and mid-ocean depths that will ultimately be exposed to warming — risking both an ocean and an atmospheric release.

These last points serve to underline some pretty basic facts, the chief of which is that pushing Nature, and heating up her life-blood world ocean waters, is a very, very dangerous game. And if this poignant new report sends any message at all it could simply boil down to this — turn back before it’s too late.

Links:

IUCN Report: Explaining Ocean Warming

Specific Heat

Ocean Warming

Awakening the Horrors of the Ancient Hothouse

LANCE MODIS

Slimy Green Algae Invades Florida

The oceans are heating up. That’s a big problem on a blue planet.

Global Warming May Dent El Niño’s Protective Hurricane Shield, Increase Droughts

Hat tip to Cate

Hat tip to George Hayduke

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Ocean Dead Zones Swirl Off Africa, Threatening Coastlines with Mass Fish Kills

The world ocean is now a region of expanding oxygen-deprived dead zones.

It’s an upshot of a human-warmed ocean system filled with high nutrient run-off from mass, industrialized farming, rising atmospheric nitrogen levels, and increasing dust from wildfires, dust storms, and industrial aerosol emissions. Warming seas hold less oxygen in solution. And the nutrient seeding feeds giant algae blooms that, when they die and decompose, further rob ocean waters of oxygen. Combined, the two are an extreme hazard to ocean health — symptoms of a dangerous transition to stratified, or worse, Canfield Ocean states.

Coastal Dead Zones -- No Fish Left

(Geographical extent of more than 405 coastal dead zones worldwide. New dead zones discovered by scientists are now traversing mid-ocean regions. Image source: No Fish Left.)

In total, more than 405 dead zones now occupy mostly coastal waters worldwide. Covering an area of 95,000 square miles and expanding, these anoxic regions threaten marine species directly through suffocation or indirectly through the growth of toxin-producing bacteria which thrive in low-oxygen environments.

Mobile, Anoxic Underwater Cyclones

Now, according to new research published in Biogeosciences, it appears that some of these dead zones have gone mobile.

The report finds zones of very low oxygen covering swirls of surface water 100-150 kilometers in diameter and stretching to about 100 meters in depth. The zones churn like whirlpools or eddies. Encapsulated in their own current of water with oxygen levels low enough to induce fish kills, these ‘dead pools’ have been discovered swirling off the coast of Africa in recent satellite photos.

The ‘dead pools’ form as strong ocean eddies break off from West African ocean currents. The eddies create mixing environments near the surface which fuels algae blooms (seen as the light blue coloration in the image below). Large algae blooms are trapped in the eddy and as the algae die, they rob the water column of oxygen. The flows of the eddy form as a kind of wall to mixing with higher oxygen surrounding waters. As a result, the oxygen readings within the dead pool plummets.

Dead Pool Eddy 2

(Newly discovered ocean dead pools like the one shown above are propagating off the coast of West Africa. These eddies are mobile dead zones of low oxygen water. A new phenomena, they represent a unique threat to ocean health in addition to the 405 other, mostly stationary, dead zones in the world’s coastal waters. Image source: Biogeosciences.)

According to lead-author Johannes Karstensen, a researcher at GEOMAR, the Helmholtz Centre for Ocean Research Kiel, in Kiel, Germany:

“The fast rotation of the eddies makes it very difficult to exchange oxygen across the boundary between the rotating current and the surrounding ocean. Moreover, the circulation creates a very shallow layer – of a few tens of meters – on top of the swirling water that supports intense plant growth. From our measurements, we estimated that the oxygen consumption within the eddies is some five times larger than in normal ocean conditions.”

Researchers found levels in these swirls to be less than 0.3 millilitres of oxygen per litre of seawater or about 1/100th the oxygen content of surrounding ocean. These are readings low enough to produce mass fish kills and to support production of toxin-producing bacteria harmful to oxygen dependent life.

Azores Downrange of Dead Pools

The zones were observed moving through the Tropical North Atlantic west of Africa. They propagated toward the north and west, finally petering out about 100 kilometers north of the Azores. This puts that East Atlantic archipelago directly in the line of fire of these new, low-oxygen eddies. A cause for concern. If one of these eddies were to enter the Azores the result could be a massive fish die off around the island chain.

Karstensen notes:

“…it is not unlikely that an open-ocean dead zone will hit the islands at some point. This could cause the coast to be flooded with low-oxygen water, which may put severe stress on the coastal ecosystems and may even provoke fish kills and the die-off of other marine life.”

Observations of these dead pools seems to indicate they are a new event. A possible result of nutrient enrichment of the surface waters in West African currents due to increased run-off or surface water nitrogen and dust seeding. As extreme rainfall events related to climate change wash more sediment down rivers and into the oceans, as more nitrogen compounds and particulate matter hit the atmosphere due to fossil fuel emissions, wildfire burning, and dust storms, and as sea level rise starts to flood nutrient-rich low lying areas, it is possible that the Tropical Atlantic dead pools represent an emerging ocean state that will grow more prevalent as time moves forward.

(UPDATED — 2037 EST, 5 May, 2015)

Links:

Dead Zones Moving West

Dead Zones Found in Atlantic Open Waters

VIMS: Dead Zones

No Fish Left

Ocean Dead Zones

Through the Looking Glass of the Great Dying

Hat Tip to Colorado Bob

Hat Tip to DT Lange

Hat Tip to Jeremy Beck

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