Feed aggregator

A new article helps scientists communicate how humans are intensifying extreme weather clearly and accurately

Climate scientists have done a great job winning the scientific arguments about climate change. To be clear about what I mean, we have done a very good job investigating whether or not the Earth’s climate is changing (it is), what is causing the change (humans), how much will it change in the future, and what will be the impacts.

There are no longer any reputable scientists who disagree with the principle view of that human emissions will cause climate change that will lead to societal and human losses (they already are). So, I use the term “win” here not to indicate it was a battle of “us” versus “them”. Rather, I mean “win” in that we have faithfully followed the scientific method, explored alternative hypotheses, checked and rechecked our work, and have come to a truth that is unassailable. We’ve done our job.

Continue reading...

Experts argue whether electric cars are worse for the environment than gas guzzlers once the manufacturing process and batteries are taken into account

Jorge Cruz has just finished his overnight shift stacking shelves at Whole Foods in Los Altos, California, and is waiting at the bus stop outside. Like much of Silicon Valley, there’s a regular flow of Tesla, BMW, Nissan and Google electric cars that cruise past from their nearby headquarters, and Cruz rather likes them.

“I really wouldn’t mind having an electric car,” he says, though his first choice is probably a Honda or an Acura. Regardless, for now, he rides the bus. “I need to save up for a car,” he explains.

Continue reading...

Ancient water channels in Morocco, declining Arctic sea ice and the US-Mexico border were among the images captured by European Space Agency and Nasa satellites last month

A bank of clouds covers East Java to the west, with a bright sun overhead casting shadows from the clouds along the ocean surface. Sunglint, an optical effect caused by the reflection of sunlight off the water surface directly back at the satellite sensor, exposes the waves created by the movement of currents in the ocean water. Internal waves are generated when the interface between layers is disturbed, such as when tidal flow passes over rough ocean floors, ridges, or other obstacles. The Lombok Strait, a relatively narrow passageway between Bali (west) and Lombok (east), allows flow of water from the Pacific Ocean into the Indian Ocean. The bottom of the strait is complex and rough, consisting of two main channels, one shallow and one deep. Because of the variation in water movement due to the complexity of the channels and ocean interface, the tides in the strait have a complex rhythm but tend to combine about every 14 days to create an exceptionally strong tidal flow. It is the combination of rough topography, strong tidal currents, and stratified water from the ocean exchange that makes the Lombok Strait famous for the generation of intensive internal waves.

Continue reading...

Chief Scientist Alan Finkel's report into the energy sector says the Paris agreement targets may not be met.

Independent review shared with agriculture ministers in May calls for an urgent $38m eradication of invasive insects

Aggressive, venomous red fire ants have the potential to be a threat in even Australia’s biggest cities and require a multimillion-dollar, 10-year program to wipe them out before it’s too late, agriculture ministers were warned in May.

An independent review into the ant, which is of South American extraction, prepared for a meeting of federal state and territory agriculture ministers in May but made public this week through the Senate, calls for a doubling of funding to $38m a year for 10 years to eliminate the scourge for good.

Continue reading...

Latest update to the red list of threatened species shows world’s tallest animal is on the brink, but some good news for Madgascan freshwater fish

The world’s tallest animal is at risk of extinction after suffering a devastating decline in numbers, with 40% of giraffes lost in the last 30 years, according to the latest “red list” analysis.

The authoritative list, compiled by the International Union for the Conservation of Nature (IUCN), has also added over 700 newly recognised bird species, but 13 of these are already extinct.

Continue reading...

Sandy, Bedfordshire The birds’ summer song has become a spit of rage, broken chirrups rendered to our ears as “get lost!”

The skylark’s summer song is reduced in winter to spits of rage, each broken chirrup rendered to human ears as “get lost!” or something far ruder. Such angry chatter broke the stillness of a recent frost-becalmed morning in the fields. The strident cries told of an aerial dogfight.

Related: David Adam on the decline of Britain's skylarks and other bird species

Continue reading...

Red fire ants could wreak more damage than rabbits, cane toads and foxes combined, experts warn.

The market is now pricing wholesale electricity contracts for next year at levels higher than what prevailed when the carbon price was in place.

QUT engineers mimic the design of a fly's eye to create a nano-material that could significantly boost solar cell efficiency.

Exclusive: Report warns investment in electricity has stalled, and existing policies won’t allow Australia to meet its Paris target

Australia’s chief scientist, Alan Finkel, has said investment in the electricity sector has stalled because of “policy instability and uncertainty” – and he’s warned that current federal climate policy settings will not allow Australia to meet its emissions reduction targets under the Paris agreement.

In a 58-page report that has been circulated before Friday’s Council of Australian Governments meeting between the prime minister and the premiers, Finkel has also given implicit endorsement to an emissions intensity trading scheme for the electricity industry to help manage the transition to lower-emissions energy sources.

Continue reading...

It's obvious there is not much rational thought in some quarters of the conservative parties, and Malcolm Turnbull will come to regret his change of tone on climate change just as Kevin Rudd did.

Oklahoma Attorney General Scott Pruitt has been tapped to run the Environmental Protection Agency in the Trump administration.

RES and Lloyds Register look at 100MW battery storage plant in South Australia - to show cheaper and more secure option than new transmission lines or gas plants.

Adelaide zoo is hoping to support 34-year-old orangutan Karta through her pregnancy as she has lost six infants in the past

A Sumatran orangutan at Adelaide zoo has fallen pregnant, despite being on contraceptives.

Karta the 34-year-old orangutan is due early in 2017. Jodie Ellen, a senior primate keeper, announced the “exciting but nerve-wracking” news on the zoo’s Facebook page. “It wasn’t a planned pregnancy,” she said. “Mother Nature actually intervened.”

Continue reading...

Sudden changes in output from ageing gas-fired generators may have worsened impact of storms in South Australia blackout, new study suggests. Inverter controlled solar, wind and storage may have ridden through the problems and kept the lights on.

AEMO report cites future of gas-powered electricity generation as “greatest variable” in fortunes of Australian gas industry.

The Minister’s Delegate has approved an update of the names for 7 species.

Sea ice covering the Arctic Ocean during the winter peak in February 2015. NASA's Scientific Visualization Studio

There is no doubt that 2016 has been a record-breaking year for Earth’s climate.

We will have to wait another couple of months for the final tally, but 2016 will be the hottest year in recorded history globally. Average temperatures are well above 1℃ warmer than a century ago.

Global average temperatures, and “global warming”, often give the impression of a gradual change in Earth’s climate occurring uniformly across the planet. This is far from the truth – particularly at the ends of the Earth. The Arctic and Antarctic are behaving very differently from the global picture.

One particular polar change that has caught the attention of scientists and the media this year has been the state of sea ice. The seasonal growth and decay of sea ice over the Arctic and Southern oceans is one of the most visible changes on Earth.

But in the past few months its seasonal progression has stalled, plunging Earth’s sea ice cover off the charts to the lowest levels on record for November. Explaining what has caused this unexpectedly dramatic downturn in sea ice is a tale of two poles.

Global sea ice area (including Antarctica and the Arctic) by year, 1977-2016. National Snow and Ice Data Centre. Wipneus/NSIDC Arctic amplifiers

The northern polar region is an epicentre for change in our warming world.

On average, the Arctic is warming at around twice the global average rate. This is due to several environmental processes in the Arctic that amplify the warming caused by rising atmospheric greenhouse gas levels.

One of these amplifiers is the sea ice itself.

As the climate warms, it’s no surprise that ice melts. What is less obvious is that when bright, white ice melts it is replaced with a dark surface (the ocean or land). Just as a black car parked in the sun will warm up faster than a white one, so the dark surface absorbs more heat from the sun than ice. This extra heat promotes more ice loss, and so the cycle goes.

This can explain the marked long-term decline of Arctic sea ice. But it can’t explain why the past month has seen such a sudden and dramatic change. For this we need to look to the weather.

Arctic climate is characterised by very large natural swings – so much so that in the past few weeks some regions of the Arctic have been a whopping 20℃ warmer than expected for this time of year.

The polar regions are separated from milder equatorial climates by a belt of westerly winds. In the northern hemisphere these winds are commonly referred to as the jet stream.

The strength of the jet stream is related to the north-to-south (cold-to-warm) gradient in northern hemisphere climate. The amplification of warming in the Arctic has reduced this gradient, and some scientists believe that this is allowing the northern jet stream to develop a more meandering path as it travels around the globe.

Jet stream winds in the northern hemisphere, November 11 2016. Screenshot from Global Forecast System/National Centres for Environmental Information/US National Weather Service.

A weaving jet stream allows warm air to penetrate further northwards over the Arctic (the flip side is that extremely cold polar air can also be pulled south over the northern hemisphere continents, causing extreme cold snaps). This appears to be responsible for the current extremely warm temperatures over the Arctic Ocean, which have caused the normal advance of winter sea ice to stall.

In effect, what we are seeing in the Arctic is the combined effect of long-term climate change and an extreme short-term weather event (which itself is probably becoming more common because of climate change).

The southern story

It’s a different story when we look at the ocean-dominated southern hemisphere.

Antarctic climate records point to a delay in some of the effects of “global warming”. The reasons are still debated, partly because of the much shorter climate records that scientists have to work with in the Antarctic.

But it is likely that the expansive Southern Ocean is an important climate change dampener that is able to “hide” some of the extra heat being absorbed by our planet beneath the ocean surface where we don’t feel it – yet.

Unlike the dramatic declines in Arctic sea ice over recent decades, the sea ice that surrounds Antarctica has been increasing slightly over the past three-and-a-half decades and 2014 set records for the most extensive Antarctic sea ice on record. So the decline in Antarctic sea ice since August this year to record low levels has come as somewhat of a surprise.

Again, the weather may hold part of the answer.

The westerly winds that circle the Southern Ocean (analogous to the northern hemisphere’s jet stream) have strengthened and moved closer to Antarctica over the past few decades. One of the effects of this has been to push sea ice away from the Antarctic continent, making for a more expansive coverage across the surrounding ocean.

But the westerly winds are fickle. They are able to change their path across the Southern Ocean very quickly. And so while the southward march in their average position over many years is clear, predicting their behaviour from month to month remains difficult. This spring the westerly winds have tended to sit closer to Australia and out of reach of Antarctica’s sea ice.

What Antarctica’s sea ice will do in the future is still an open question. Climate models indicate that Antarctica won’t remain protected from global warming forever, but just if and when this might cause Antarctica’s sea ice to replicate the Arctic sea ice loss is still anyone’s guess.

Lessons in the madness

Extreme years, such as 2016, are important as they provide glimpses of what the new normal of our climate system may look like in the not-too-distant future.

But these pointers to where we are going also need to be assessed in terms of where we have come from. For sea ice, logbooks from the age of heroic exploration suggest that the Antarctic system is mostly still operating within its normal bounds.

The same cannot be said for the Arctic. The decline of sea ice there has been likened to a ball bouncing down a bumpy hill – some years it will bounce higher than others, but eventually the ball will reach the bottom.

When it does, the Arctic Ocean will be ice-free in summer. That’s a boon for shipping, but don’t expect to see any polar bears on those Arctic cruises.

Nerilie Abram receives funding from the Australian Research Council.

Monash University issues $218m Climate Bond – a world first, targeting sustainable development in the tertiary education sector.