Earth is ‘twice as dusty’ now as it was 100 years ago

If the house seems dustier than it used to be, it may not be a reflection on your housekeeping skills.

The amount of dust in the Earth's atmosphere has doubled over the last century, according to a new study by U.S. scientists.

And the increase could be a contributing factor to climate and ecology changes around the world.

Dust to dust: Using computer models, scientists have been able to work out how dust levels have changed in the last 100 years

To measure fluctuations in desert dust over the last century, researchers collected existing data from ice cores, lake sediment and coral, each of which contains information about past concentrations of desert dust in the region.

They then linked each sample with its likely source region and calculated the rate of dust deposition over time.

Applying components of a computer modeling system known as the Community Climate System Model, the researchers reconstructed the influence of desert dust on temperature, precipitation, ocean iron deposition and terrestrial carbon uptake over time.

Dry subject: But desert dust has an effect on temperature, precipitation, ocean iron deposition and terrestrial carbon uptake, according to researchers

They found that regional changes in temperature and precipitation caused a global reduction in terrestrial carbon uptake of six parts per million (ppm) over the 20th century.

The model also showed that dust deposited in oceans increased carbon uptake from the atmosphere by six percent, or four ppm, over the same time period.

While the majority of research related to aerosol impacts on climate is focused on anthropogenic aerosols - those directly emitted by humans through combustion - lead scientist NatalieMahowald told ScienceDaily that the study highlights the important role of natural aerosols as well.

'Now we finally have some information on how the desert dust is fluctuating. This has a really big impact for the understanding of climate sensitivity,' she said.

The sun rises two days early in Greenland, sparking fears that climate change is accelerating

The sun over Greenland has risen two days early, baffling scientists and sparking fears that Arctic icecaps are melting faster than previously thought.

Experts say the sun should have risen over the Arctic nation's most westerly town, Ilulissat, yesterday, ending a month-and-a-half of winter darkness.

But for the first time in history light began creeping over the horizon at around 1pm on Tuesday - 48 hours ahead of the usual date of 13 January.

The mysterious sunrise has confused scientists, although it is believed the most likely explanation is that it is down to the lower height of melting icecaps allowing the sun's light to penetrate through earlier.

Climate change? The sun rose in Ilulissat, Greenland, two days early on Tuesday, ending a month-and-a-half of winter darkness. One theory is that melting ice caps have lowered the horizon allowing the sun to shine through earlier

Thomas Posch, of the Institute for Astronomy of the University of Vienna, said that a local change of the horizon was 'by far the most obvious explanation'.

He said as the ice sinks, so to does the horizon, creating the illusion that the sun has risen early.

This theory, based on the gradual decline of Greenland's ice sheet, is backed by recent climate studies.

A report by the World Meteorology Organisation shows that temperatures in Greenland have risen around 3C above average over the last year.

It also reported that December was much warmer than usual with rainfall instead of snow recorded for the first time in Kuujjuaq since records began.

Low horizon: The fishing town of Ilulissat is Greenland's most westerly habitation. Temperatures in Greenland have risen 3C above average over the last year

It has even been suggested that the sun's early appearance could have an astronomical explanation.

But Wolfgang Lenhardt, director of the department of geophysics at the Central Institute for Meteorology in Vienna, scotched this theory.

He said: 'The constellation of the stars has not changed. If that had happened, there would have been an outcry around the world.

'The data of the Earth's axis and Earth's rotation are monitored continuously and meticulously and we would know if that had happened.'

You may not believe it, but 2010 was the hottest year since records began in 1880

After another washout summer and the Arctic conditions of last month you'd be forgiven for thinking 2010 was a touch colder than normal.

But last year was the joint warmest globally since records began in 1880, according to climate experts at Nasa.

Scientists at the U.S. space agency and the National Climatic Data Center (NCDC) agreed that the average worldwide temperature in 2010 was 1.12F (0.62C) above normal.

The measurement equals the record set in 2005.

Climate change? Last year equalled 2005 as the warmest globally since records began in 1880, scientists said

ARE COLD WINTERS THE FLIP SIDE OF CLIMATE CHANGE?

Bitterly cold winters in Europe and the U.S. in 2010 may be a paradoxical side effect of climate change, some scientists said.

Rising temperatures mean a shrinking of sea ice in the Arctic, heating the region and pushing cold air southwards during the winter, according to a study last month in the Journal of Geophysical Research.

Warming of the air over the Barents and Kara seas, for instance, seems to bring cold winter winds to Europe.

'This is not what one would expect,' said Vladimir Petoukhov, lead author of the study and climate scientist at Germany's Potsdam Institute for Climate Impact Research.

'Whoever thinks that the shrinking of some far away sea-ice won't bother him could be wrong.'

The release of the NOAA report itself was delayed one day by an unusually hard snowstorm in North Carolina.

'These anomalies could triple the probability of cold winter extremes in Europe and northern Asia,' he said.

'Recent severe winters like last year's... do not conflict with the global warming picture, but rather supplement it.'

Most atmospheric scientists attribute the change to gases released into the air by industrial processes and gasoline-burning engines.

David Easterling, the chief of the scientific services division at the NCDC, said: 'These results show that the climate is continuing to show the influence of greenhouse gases. It's showing evidence of warming.'

Last year was also the wettest on record and a warmer atmosphere holds more water, which in general can result in more floods, he said.

The report did not predict weather in the future. But the U.N. climate science panel said weather is likely to be more extreme this century because of a build up of gases released by burning fossil fuels and forest destruction.

James Hansen, the director of NASA's Goddard Institute for Space Studies, said 'if the warming trend continues, as is expected, if greenhouse gases continue to increase, the 2010 record will not stand for long'.

His office also released a report on Wednesday that said 2010 was tied for the warmest year on record with 2005.

Jay Gulledge, the senior scientist at the Pew Center on Global Climate Change, said farmers and others can adjust to expected warmer temperatures, but preparing for extreme weather is harder.

He said: 'We've got really immense potential right now to have even bigger impacts from the direct effects of extreme events.'

As the weather warmed, the world did not do enough to prevent future climate change, scientists said.

At U.N. climate talks in Cancun late last year nearly 200 countries agreed to set a target of limiting a rise in average world temperatures to below 2C (3.6F) over pre-industrial times.

But promised emissions curbs by big polluters such as China and the U.S. are not enough to achieve that goal and tougher actions are needed, climate scientists said.

Sun worship: As the weather has warmed, the world did not do enough to prevent future climate change, scientists said

The UK Met Office's Hadley Centre and the U.N.'s World Meteorological Organization are expected to issue reports on global 2010 temperatures later this month.

Many places, such as Russia and Pakistan, suffered from heat waves and floods that killed thousands, scorched crops and inundated countless farm acres.

Those events, caused in part by a shifted jet stream in the atmosphere, helped lead to record global food prices and threaten to lead to food riots like those seen in 2008.

It's not possible to directly link global warming as the cause of one weather event. But the trend of rising temperatures since 2000 increases the possibility of extreme weather events such as heat waves, droughts and floods, Dr Easterling said.

Every year since 2000 has ranked as one of the 15 warmest years on record, he said.

World faces overpopulation 'disaster' as number of people is set to rise by 75 million EACH YEAR

• Global population is expected to peak at 9.5bn in 2075
• Annual rise is the equivalent of entire UK population
  

The world is edging closer to overpopulation Armageddon as swelling cities drain the planet of its vital resources, a report warns today.

Population growth, especially in newly developing countries, is the 'defining challenge of the 21st century'.

It represents a greater potential threat than climate change, according to the Institution of Mechanical Engineers.

Only way is up? Population growth is the 'defining challenge of the 21st century' and represents a potential greater threat than climate change

Over the next six decades the world's population is expected to explode, soaring from 6.9billion to peak at 9.5billion in 2075, the report says.

Each year the number of people in the world is due to rise by 75million - equivalent to the entire population of the UK.

Most of the growth will be in the African continent, which is following in the industrial footsteps of Asia, and in cities.

The world's urban population is likely to increase from a 2007 figure of 3.3billion to 6.4billion in 2050.

But without drastic changes there will not be sufficient resources to provide people with basic human needs such as water, food, energy and shelter, says the report, entitled Population: One Planet, Too Many People?

Climate change is likely to place even more stress on resources, resulting in as many as a billion people moving from inhospitable regions.

Water requirements are projected to rise by 30 per cent by 2030 while food resources will be stretched by a doubling of demand for agricultural produce by 2050.

Slum living, already forced on a third of the world's urban populations, will become even more widespread as cities became increasingly packed with people.

As a result billions could be at risk of hunger, thirst and appalling living conditions, creating tinderbox conditions that could ignite civil unrest and conflict.

'Staggering' rise: The world's urban population is likely to increase from a 2007 figure of 3.3billion to 6.4billion in 2050

The report, compiled with the help of more than 70 engineers around the world, sets out a series of 'engineering development goals' as a first step towards averting the looming disaster.

It calls for a global engineering initiative, modelled on the United Nations' Millennium Development Goals, to tackle the key problem areas of energy, water, food, urbanisation and finance.

Lead author Dr Tim Fox said: 'Towards the end of the century the world is going to come face to face with the challenges of the largest population explosion in human history.

'These headline figures really are staggering from a resources point of view and for the provision of the basic needs of human society.'

Engineering solutions such as reducing energy waste, improving food storage and extracting water from underground aquifers would allow the world to sustain a population of 9.5billion, said Dr Fox.

The cost would run into many trillions of pounds, but would be affordable if richer nations were willing to share financial as well as technological resources.

A key necessity is to help poorer nations 'leapfrog' the resource-hungry 'dirty' phase of industrialisation.

As population levels soar in newly emerging industrialised countries, those in developed parts of the world such as the UK and US are likely to stabilise or even fall, said the report.

The population of Europe is expected to decline by 20 per cent by 2050. However, the impact of global population growth would still be felt around an increasingly connected world where changes in one region could have an impact 'many thousands of miles away'.

Sea levels will rise by at least 13ft in next 1,000 years, claim scientists

Global sea levels will rise by at least 13ft in the next 1,000 years as a result of carbon dioxide emissions, scientists have warned.

The 'unstoppable' impact of global warming is expected to cause a catastrophic collapse of the West Antarctic ice sheet by the year 3000.

The gloomy prediction is a 'best case' scenario, assuming that all use of fossil fuels ceases and no more carbon dioxide is pumped into the atmosphere.

In fact, the true effects of climate change 'inertia' might be much worse, scientists claimed yesterday.

Floating iceberg: Scientists have warned that the 'unstoppable' impact of global warming will cause a collapse of the West Antarctic ice sheet by the year 3000

The study, published in the journal Nature Geoscience, is the first to make climate predictions looking ahead 1,000 years.

The scientists carried out computer simulations exploring zero-emission scenarios beginning in 2010 and 2100.

Northern hemisphere regions fared better than the south, with climate change patterns eventually reversing in places such as Canada.

But at the same time parts of north Africa were turned to desert as land dried out by up to 30 per cent, and ocean warming of up to 5 per cent triggered the collapse of the West Antarctic ice sheet - a region the size of the Canadian prairies.

Study leader Professor Shawn Marshall, from the University of Calgary in Canada, said: 'The global ocean and parts of the southern hemisphere have much more inertia, such that change occurs more slowly.

'The inertia in intermediate and deep ocean currents driving into the southern Atlantic means those oceans are only now beginning to warm as a result of CO2 emissions from the last century.

'The simulation showed that warming will continue rather than stop or reverse on the 1,000-year time scale.'

Wind currents in the southern hemisphere could also have an impact, said Professor Marshall. Southern winds tend to strengthen and stay strong without reversing.

He said: 'This increases the mixing in the ocean, bringing more heat from the atmosphere down and warming the ocean.'

The scientists plan to carry out a more thorough assessment of how long it might take for the West Antarctic ice sheet to disintegrate.