A British man in the Mexican tourist area of Cancun is looking to get legal recognition for the island home that he has built almost entirely out of recycled materials.
Thursday, April 07, 2016
War threatens world's largest gorilla
Numbers of the world's largest type of gorilla, the Grauer's gorilla, have fallen dramatically.
The gorilla is now considered "critically endangered" which means they might soon be totally wiped out.
Where do they live?
The gorilla lives in the eastern part of the Democratic Republic of Congo, in central Africa.
The number of gorillas there has fallen from 17,000 in 1994 to just 3,800 today.
Why is it happening?
War in the the Democratic Republic of Congo has affected the number of Grauer's gorillas living there.
The forests where they live are being destroyed because of the fighting.
They have also been illegally hunted for their meat because in some areas there is not enough food to eat.
From CBBC Newsround
Cutting food and carbon waste-lines for healthy climate
Reducing food waste and changing the way people consume calories will help deliver a sustainable food system and reduce emissions, a study suggests.
An estimate one third of all food produced remains uneaten
The global demand for food could more than double by the middle of the century, yet an estimated one third of produce is lost or wasted each year.
By cutting this waste will help food security and reducing agriculture's climate burden, the researchers added.
The findings appear in the journal Environmental Science & Technology.
As the global human population is set to reach in excess of nine billion people by the middle of this century, up from the current seven billion, the importance of reducing food loss and waste in order to deliver food security is well documented.
However, a team of scientists have also considered what steps need to be taken to tackle food production's contribution to global carbon emissions.
Shifts in lifestyle and diet is increasing the global impact of the food sector
Prof Jurgen Kropp from the Potsdam Institute for Climate Impact Research, Germany, one of the study's co-authors said that previous studies had highlighted that "agriculture was playing an increasingly important role when it came to carbon dioxide emissions".
"We have worldwide lifestyle changes where people are moving towards a meat-rich diet and we need more food, of course," he told BBC News.
"The more rich a country becomes, there is a move towards more meat-rich diets and, of course, more calorie-rich diets.
"For one calorie of meat, you have to utilise one to eight calories of cereal. It is an inefficient form of food production," he observed.
"On the other hand, rich countries are wasting more food. A lot of the food we are producing at the moment, we do not see on our plates."
Prof Kropp added that this trend was projected to have a considerable impact on the global carbon budget by the middle of the 21st Century.
They calculated that about 10% of global greenhouse gas emissions from agriculture could be traced back to food waste by 2050.
However, the team examined past datasets and used future scenarios to identify pathways that could deliver improvements in food security and CO2 emissions.
As people around the globe shift to more meat-rich diets, emissions from agriculture continue to rise
The team observed: "The global food requirement changed from 2,300 [calories per person each day] to 2,400 [calories per person each day] during the past 50 years, while the food surplus grew from 310 [calories per person each day] to 510 [calories per person each day]."
Over the same period, the team found that greenhouse gas emissions associated with food surplus increased from 130 million tones of CO2 equivalent per year to 530 million tonnes - an increase of more than 300%.
Future scenarios did not make comfortable reading. They calculated that emissions associated with the food wasted may "increase tremendously" to up to 2.5 giga-tonnes of CO2 equivalent per year.
Prof Kropp added: "As many emerging economies like China or India are projected to rapidly increase their food waste as a consequence of changing lifestyle, increasing welfare and dietary habits towards a larger share of animal-based products, this could over proportionally increase greenhouse-gas emissions associated with food waste [while] undermining efforts for an ambitious climate protection.
"Avoiding food loss could pose a leverage to various challenges at once, reducing environmental impacts of agriculture, saving resources used in food production, and enhance local, regional, and global food security."
From BBC News Science / Environment
Sunday, April 03, 2016
'Drastic' Antarctic melt could double global sea-level rise
Global sea levels could rise by more than double the current best estimate, according to a new analysis of climate change in Antarctica.
The latest model suggests that Antarctic melting could double projections of sea-level rise
The modelling assessment says that Antarctic melting alone could contribute more than a metre to sea level by the end of this century.
By 2500, according to the study, the same source could cause levels across the world to rise by 13m.
The authors say that rapid cuts in carbon emissions could limit this risk.
Competing ideas
In 2013, the Intergovernmental Panel on Climate Change (IPCC) predicted that, without any restrictions on carbon emissions, the seas around the world likely rise by up to 98cm by 2100.
However, the IPCC estimates contained a minimum contribution from Antarctica.
Other analyses since then have projected bigger increases, with a recent studysuggesting that the oceans were rising faster than at any time in the past 2,800 years and by 2100 they could be up to 1.31m higher.
The exact level of Antarctica's impact on these projections has been vigorously debated. Late last year, a research paper suggested that projections of a contribution of a metre or more were not plausible.
But this new study argues that by 2100 the world could see 1.14m of sea-level rise from Antarctica alone.
Additions to the model
The scientists say that their model is able to provide a more accurate prediction because it incorporates the impacts of some physical processes for the first time.
While other models have focussed on the impact of warmer waters melting the ice shelves from below, this new study also includes the effect of surface melt-water and rain trickling down from above and fracturing supporting ice, hastening its slide to the sea.
The model also calculates the impact of the disintegration of floating ice shelves. If this happens, it will reveal walls of ice so tall that they cannot support their own weight.
The scientists involved expect that these extra factors will kick in over the coming decades, as warming from the atmosphere (not just from warmer waters below) becomes the dominant driver of ice loss.
The collapse of ice cliffs could be a significant factor in the new projection
"One reason that other models didn't include the atmospheric warming is because it hasn't started to happen just yet," said co-author Dr David Pollard from Penn State University, US.
"In Antarctica, around the edges at sea level, it's just beginning to get up to the melt point in summer.
"With that warming, the flanks of Antarctica will start to melt drastically in about 50 to 100 years - and then it will start to kick in according to our model."
The authors believe that they have demonstrated the accuracy of the new model by correctly replicating sea-level rise in warm periods, millions of years into the past.
"Recently, we looked at the long-standing problem posed by geological evidence that suggests sea level rose dramatically in the past, possibly up to 10 to 20 metres around 3 million years ago, in the Pliocene," said Dr Pollard.
"Existing models couldn't simulate enough ice-sheet melting to explain that."
'Right questions'
If the world continues to emit "business as usual" levels of carbon dioxide over the coming decades, the scientists argue that sea-level rise will be double what has already been estimated for the coming 100 years.
"If these processes do kick in and they end up being as important as we think that they could be, then they really do have a big impact," said Prof Robert DeConto from the University of Massachusetts, Amherst.
"West Antarctica is responding very soon in these simulations and that ends up having a big impact on North America in particular."
Other researchers have praised the development of the new model for including impacts such as surface melt water and ice-cliff collapse, but they are uncertain about the conclusions.
"I have no doubt that on a century to millennia timescale, warming will make these processes significant in Antarctica, as well as Greenland, and drive a very significant Antarctic contribution to sea-level rise," commented Prof David Vaughan of the British Antarctic Survey.
"The big question for me is, how soon could this all begin, and could it be early enough to drive substantially higher sea levels by 2100? I'm not sure, but these guys are definitely asking the right questions."
The authors believe that there is "good news" in their report. If global emissions of carbon are curtailed significantly then the extra factors that substantially boost Antarctic melting will be avoided.
Seas will continue to rise, but not at the runaway rates suggested by this paper,which has been published in the journal Nature.
From BBC news-Science/ Environment
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