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Global warming is melting the Greenland Ice Sheet, fast | John Abraham
The Greenland Ice Sheet is losing 110,000 Olympic size swimming pools worth of water each year.
A new study measures the loss of ice from one of world’s largest ice sheets. They find an ice loss that has accelerated in the past few years, and their measurements confirm prior estimates.
As humans emit heat-trapping gases, we expect to see changes to the Earth. One obvious change to be on the lookout for is melting ice. This includes ice atop mountains, ice floating in cold ocean waters, and the ice within large ice sheets or glaciers. It is this last type of ice loss that most affects ocean levels because as the water runs into the oceans, it raises sea levels. This is in contrast to melting sea ice – since it is already floating in ocean waters, its potential to raise ocean levels is very small.
Continue reading...Oil, gas and marine parks really can coexist in our oceans – here's how
When it comes to conserving the world’s oceans, bigger isn’t necessarily better. Globally, there has been an increasing trend towards placing very large marine reserves in remote regions. While these reserves help to meet some conservation targets, we don’t know if they are achieving their ultimate goal of protecting the diversity of life.
In 2002, the Convention on Biological Diversity called for at least 10% of each of the world’s land and marine habitats to be effectively conserved by 2010. Protected areas currently cover 14% of the land, but less than 3.4% of the marine environment.
Australia’s marine reserve system covers more than a third of our oceans. This system was based on the best available information and a commitment to minimising the effects of the new protected areas on existing users. However, since its release the system has been strongly criticised for doing little to protect biodiversity, and it is currently under review.
In a new study published in Scientific Reports, we looked at the current and proposed marine reserves off northwest Australia – an area that is also home to significant oil and gas resources. Our findings show how conservation objectives could be met more efficiently. Using technical advances, including the latest spatial modelling software, we were able to fill major gaps in biodiversity representation, with minimal losses to industry.
A delicate balanceAustralia’s northwest supports important habitats such as mangrove forests, seagrass beds, coral reefs and sponge gardens. These environments support exceptionally diverse marine communities and provide important habitat for many vulnerable and threatened species, including dugongs, turtles and whale sharks.
This region also supports valuable industrial resources, including the majority of Australia’s conventional gas reserves.
A 2013 global analysis found that regions featuring both high numbers of species and large fossil fuel reserves have the greatest need for industry regulation, monitoring and conservation.
Proposed and existing state and Commonwealth marine reserves in northwest Australia shown in relation to petroleum leases. Cordelia Moore Conservation opportunititesNot all protected areas contribute equally to conserving species and habitats. The level of protection can range from no-take zones (which usually don’t allow any human exploitation), to areas allowing different types and levels of activities such tourism, fishing and petroleum and mineral extraction.
A recent review of 87 marine reserves across the globe revealed that no-take areas, when well enforced, old, large and isolated, provided the greatest benefits for species and habitats. It is estimated that no-take areas cover less than 0.3% of the world’s oceans.
In Australia’s northwest, no-take zones cover 10.2% of the area, which is excellent by world standards in terms of size. However, an analysis of gaps in the network reveal opportunities to better meet the Convention on Biological Diversity’s recommended minimum target level of representation across all species and features of conservation interest.
We provided the most comprehensive description of the species present across the region enabling us to examine how well local species are represented within the current marine reserves. Of the 674 species examined, 98.2% had less than 10% of their habitat included within the no-take areas, while more than a third of these (227 species) had less than 2% of their habitat included.
Into the abyssFew industries in this region operate in depths greater than 200 metres. Therefore, the habitats and biodiversity most at risk are those exposed to human activity on the continental shelf, at these shallower depths.
However, the research also found that three-quarters of the no-take marine reserves are sited over a deep abyssal plain and continental rise within the Argo-Rowley Terrace (3,000-6,000m deep). These habitats are unnecessarily over-represented (85% of the abyss is protected), as their remoteness and extreme depth make them logistically and financially unattractive for petroleum or mineral extraction anyway.
The majority of the no-take marine reserves lie over a deep abyssal plain. Cordelia MooreProposed multiple-use zones in Commonwealth waters provide some much-needed extra representation of the continental shelf (0-200m depth). However, all mining activities and most commercial fishing activities are permissible pending approval. This means that the management of these multiple-use zones will require some serious consideration to ensure they are effective.
A win for conservation and industryAn imbalance in marine reserve representation can be driven by governments wanting to minimise socio-economic costs. But it doesn’t have to be one or the other.
Our research has shown that better zoning options can maximise the number of species while still keeping losses to industry very low. Our results show that the 10% biodiversity conservation targets could be met with estimated losses of only 4.9% of area valuable to the petroleum industry and 7.2% loss to the fishing industry (in terms of total catch in kg).
Examples of how the no-take reserves could be extended or redesigned to represent the region’s unique species and habitats. Cordelia MooreManagement plans for the Commonwealth marine reserves are under review and changes that deliver win-win outcomes, like the ones we have found, should be considered.
We have shown how no-take areas in northwest Australia could either be extended or redesigned to ensure the region’s biodiversity is adequately represented. The cost-benefit analysis used is flexible and provides several alternative reserve designs. This allows for open and transparent discussions to ensure we find the best balance between conservation and industry.
Cordelia Moore has received funding from the University of Western Australia, the Australian Institute of Marine Science and CSIRO.
Clay Bryce receives funding from the Western Australian Museum and Woodside Energy.
Hugh Possingham receives funding from The Australian Research Council, The Department of The Environment (Australia) and a lot of other groups. He is affiliated with the Wentworth Group of Concerned Scientists, Bush Heritage Australia and sits on heaps of boards and committees.
Oliver Berry receives funding from The Western Australian Marine Science Institution.
Romola Stewart has previously received funding from PEW Charitable Trusts Australia.
Ben Radford does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond the academic appointment above.
Research Filter: Proxima b, global warming and the Zika virus
Of hungry badgers and hidden worms
Old Warden, Bedfordshire In this parched landscape it was clear the hedgerow fruit had not ripened a moment too soon for the badgers
It took only a few dry weeks for the fields on the plateau above the village to forget that it had ever rained. The clay soil was beginning to crack, the footpath had turned to a sun-baked dirt track and there was no yield underfoot. Every bump and stone was hard and uncompromisingly contoured, jabbing at an instep, stubbing a toe.
The worms had become dustbowl refugees in this parched landscape, sinking deep underground. Far below my feet, they would be aestivating, bunched up in knots, coated in their own mucus in a hibernation-like suspension of active life, waiting for moisture to come again.
Continue reading...What will COAG reforms mean for Australia’s gas ringmaster?
US solar PV prices hit “all-time low”, at rooftop and utility-scale
CSIRO-made smart solar and storage system launched by Evergen
What does the Paris 1.5˚C warming limit mean for Australia?
ACCC says it’s OK for big utilities to use their market power
Cross currents hit India Government’s grand coal expansion plans
Industrial Revolution kick-started global warming much earlier than thought
154 Australian scientists demand climate policy that matches the science
Climate scientists write another letter warning of unfolding crisis for Turnbull to ignore
More than 150 leading climate scientists at universities and government agencies ask for cuts to coal exports, saying: ‘There is no Planet B’
I’m guessing that Malcolm Turnbull gets a fair few letters on any given day. You wonder how he has the time to read them all.
How do you prioritise the ones worth your attention, and the ones that you can toss in the round-shaped filing cabinet under your desk?
Continue reading...Pneumatic octopus is a first for soft robotics
Meet the octobot: A first for soft robotics
Climate warming 'started about 180 years ago'
Seeking ET
The Industrial Revolution kick-started global warming much earlier than we realised
In the early days of the Industrial Revolution, no one would have thought that their burning of fossil fuels would have an almost immediate effect on the climate. But our new study, published today in Nature, reveals that warming in some regions actually began as early as the 1830s.
That is much earlier than previously thought, so our discovery redefines our understanding of when human activity began to influence our climate.
Determining when global warming began, and how quickly the planet has warmed since then, is essential for understanding how much we have altered the climate in different parts of the world. Our study helps to answer the question of whether our climate is already operating outside thresholds that are considered safe for human society and functional ecosystems.
Our findings show that warming did not develop at the same time across the planet. The tropical oceans and the Arctic were the first regions to begin warming, in the 1830s. Europe, North America and Asia followed roughly two decades later.
Surprisingly, the results show that the southern hemisphere began warming much later, with Australasia and South America starting to warm from the early 20th century. This continental-scale time lag is still evident today: while some parts of Antarctica have begun to warm, a clear warming signal over the entire continent is still not detectable.
The warming in most regions reversed what would otherwise have been a cooling trend related to high volcanic activity during the preceding centuries.
Global warming got underway much earlier in the north.By pinpointing the date when human-induced climate change started, we can then begin to work out when the warming trend broke through the boundaries of the climate’s natural fluctuations, because it takes some decades for the global warming signal to “emerge” above the natural climate variability.
According to our evidence, in all regions except for Antarctica, we are now well and truly operating in a greenhouse-influenced world. We know this because the only climate models that can reproduce the results seen in our records of past climate are those models that factor in the effect of the carbon dioxide released into the atmosphere by humans.
These remarkable findings were pieced together from the most unusual of sources – not thermometers or satellites, but rather from natural climate archives. These include coral skeletons, ice cores, tree rings, cave deposits and ocean and lake sediment layers, all of which record the climate as they grow or accumulate.
These archives provide long records that extend back 500 years – well before the Industrial Revolution – and provide a critical baseline for the planet’s past climate, one that is impossible to obtain otherwise.
But why is there no clear warming fingerprint yet seen across Antarctica? The answer most likely lies in the vast Southern Ocean, which isolates the frozen continent from the warming happening elsewhere.
The westerly winds that circulate through the Southern Ocean around Antarctica keep warm air masses from lower latitudes at bay. Ozone depletion and rising greenhouse gas concentrations during the 20th century have also caused this wind barrier to get stronger.
The Southern Ocean currents that flow around Antarctica also tend to move warmer surface waters away from the continent, to be replaced with cold deeper water that hasn’t yet been affected by surface greenhouse warming. This process could potentially delay Antarctica’s warming by centuries.
Ocean insulationThe delay in warming observed in the rest of the southern hemisphere is something we do not yet fully understand. It could simply be because fewer records are available from the southern hemisphere, meaning that we still don’t have a full picture of what is happening.
Alternatively, like Antarctica, the southern hemisphere’s oceans could be holding back warming – partly through winds and currents, but perhaps also because of “thermal inertia”, whereby the ocean can absorb far more heat energy than the atmosphere or the land before its temperature markedly increases. Bear in mind that the southern half of the globe has much more ocean than the north.
Essentially, then, the coolness of the southern hemisphere’s vast oceans could be “insulating” Australasia and South America from the impact of global warming. The question is, for how long?
If our evidence of delayed warming in the southern hemisphere holds true, it could mean we are in in for more climate surprises as global warming begins to overcome the thermal inertia of our surrounding oceans. Could the recent record warming of Australian waters, and the subsequent damage to the Great Barrier Reef, be an early sign that this is already occurring?
Recent research suggest that the mass bleaching event of the reef was made 175 times more likely by climate change. Following the recent severity of such extremes, a better understanding of how anthropogenic greenhouse warming is already impacting the southern hemisphere is critical.
What to do about itLeading scientists from around the world met in Geneva last week to discuss the goal of limiting average global warming to 1.5℃ – the more ambitious of the two targets enshrined in the Paris climate agreement.
Last year, global temperatures crossed the 1℃ threshold, and 2016 is on track to be 1.2-1.3℃ above our climate baseline.
But here’s the kicker. That baseline is relative to 1850–1900, when most of our thermometer-based temperature records began. What our study shows is that for many parts of the world that estimate isn’t good enough, because global warming was already under way, so the real baseline would be lower.
The small increases in greenhouse gases during the 19th century had a small effect on Earth’s temperatures, but with the longer perspective we get from our natural climate records we see that big changes occurred. These fractions of a degree of extra warming might seem insignificant at first, but as we nudge ever closer to the 1.5℃ guardrail (and potentially beyond), the past tells us that small changes matter.
Helen McGregor will be online to answer your questions from 2pm AEST today. Post a query in the comments below.
Helen McGregor receives funding from the Australian Research Council and the University of Wollongong, Australia.
Joelle Gergis receives funding from the Australian Research Council.
Nerilie Abram receives funding from the Australian Research Council.
Steven Phipps receives funding from the Australian Antarctic Science Program, the Australian Research Council, the International Union for Quaternary Research, the National Computational Infrastructure Merit Allocation Scheme, the New Zealand Marsden Fund, the University of Tasmania and UNSW Australia.