Combined global land and sea-surface temperatures in March were 1.22 degrees above the 20th-century average, beating the previous record for the month - set just a year earlier - by almost one-third of a degree, the US National Oceanic and Atmospheric Administration said. Each of the past 11 months have now broken global temperature records, the longest such streak in the agency's 137 years of data collection.

Land surface temperatures for March, though, were 2.33 degrees above the 20th-century average, smashing the previous March record set in 2008 by 0.43 degrees. It was also the most unusually warm reading for any month, eclipsing February, NOAA said.

The record breaking conditions come as leaders of 150-plus nations are due to gather in New York this week to ratify the global climate pact agreed in Paris in late 2015 to limit global warming to 1.5-2 degrees, compared with pre-industrial times.

Read more: http://www.smh.com.au/environment/climate-change/worse-things-in-store-steaming-hot-world-sets-more-temperature-records-20160419-goaf58.html#ixzz46LE1Tj61
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"We're still missing the significant cold fronts that are normally due this time of the year," said Brett Dutschke, senior meteorologist with Weatherzone.

A cold front will bring some rain for the city on Saturday and early Sunday but temperatures should pick up again after Monday, he said.

Tuesday may be the warmest in the near future, with a top of 28 degrees in the city and 30 tipped for Penrith, the Bureau of Meteorology said.

Sydney's temperatures are running about 2 degrees warmer than average for April for both daytime and nighttime. Minimum temperatures for the first 24 days of the month were all warmer than usual.

Many other cities are also on the warm side, with Hobart's 25.3 degrees on Tuesday the warmest it has been this late in the season for 11 years. Adelaide exceeded 30 degrees, with similar conditions tipped for Wednesday.

"This week's temperatures through south-eastern Australia are likely to be well above normal," said Blair Trewin, senior climatologist with the bureau, said.

Nationally, this April will "very likely" be the second warmest on record, trailing only the balmy April 2005, when records were broken by about 1 degree, Dr Trewin said.

Parts of northern Australia have been one source of the unusual heat, with a weak wet season leading to clearer skies and the prospect of a few record temperatures for so late in the year.

Also, the vegetation is drier than usual, reducing the evaporative cooling effect, Dr Trewin said.

read more: http://www.smh.com.au/environment/weather/sydney-weather-warm-weather-to-extend-well-into-may-as-nation-heats-up-20160426-gofb0x.html

 

 

Greenland's ice is melting

Scientists set up camp on the ice of Greenland, in the hope to capture the first comprehensive measurements of the rate of melting ice. Their research could yield valuable information to help figure out how rapidly sea levels will rise in the 21st century.

PT0M39S 620 349

• Scorching start to 2016
• Emerging threat in the oceans

In a year of startling data pointing to a warming world, the thin blue line in the chart of Greenland's ice melt was initially dismissed as just too outlandish to be accurate.

Greenland is home to the world's second largest ice mass, containing enough water to lift average sea levels about seven metres if it all melted.

So in early April, signs that the giant ice sheets were melting at least a month earlier than typical during the three decades-plus of reliable records stunned scientists at the Danish Meteorological Institute.
"We had to check that our models were still working properly" Peter Langen, a climate scientist at DMI, told Polar Portal earlier this month.And they were.

Warm air sweeping in from the south-west of Greenland had prompted more than 12 per cent of the ice sheet to register melting.

Weather stations 1840 metres above sea-level reported temperatures of above 3 degrees, conditions that would be considered a warm day in July, let alone April.

"Everything is melting", said Aqqaluk Petersen, a resident of Nuuk, Greenland's capital. 

The heatwave, Greenland style, added to other evidence that the top of the world continues to warm about twice as fast as the rest of the planet. 

'The big show'

"Greenland is really the big show when it comes to ice melt," said Matt King, Professor of Polar Geodesy and an ARC Future Fellow at the University of Tasmania. "It's probably losing as much ice as all the small glaciers around the world combined, and probably more than Antarctica.

"Greenland is being eaten away from away from above and from the edges."

Arctic air temperatures have risen about two degrees since the 1960s. Ocean temperatures are also warming, thawing Greenland glaciers in contact with surrounding seas.

Since satellite records date only from the 1970s, some natural fluctuations may be in play, he said. Still, Greenland's early April warmth was consistent with other signals of a warming planet.

"Such a big spike in melting so early is in complete agreement with what you'd expect when we heat the atmosphere so much," Professor King said, referring to the impact from humans burning fossil fuels and releasing other greenhouse gases.

The Arctic sea ice, for instance, also set a record low maximum range this year, setting up a shorter-than-usual melt season in spring and summer, according to the US National Snow and Ice Data Center. Less ice also fosters more warming since there is less reflection of solar radiation back into space, with more of the warmth absorbed by the now ice-free waters.

Warmer conditions mean there are more days when polar temperatures are positive, meaning that they is more melting of surface ice.

Sea-level impact

While April's early warm spurt in Greenland eased back, the loss of ice mass has continued, running at about two months ahead of the average for the period since 1990, according to the DMI.

For the 2003-2011 period, Greenland net annual ice loss was 234 cubic km of water. That's enough to lift global sea levels by an average of 0.65 mm, the DMI said.

"This process of mass loss started around 1990 and has accelerated since the year 2000," the Polar Portal said. "The mass loss in recent years is approximately four times greater than it was before 2000."

Professor King said that one effect of early melting is that the surface snow turns to water, exposing the darker glacial ice below. That ice has a lower albedo effect, trapping in more warmth and adding to the melting trend.

The warm start to April, meanwhile, has continued for much of the month, leaving Greenland on course for a month well-above normal temperatures:

Updated April surface temperature anomalies show nearly all of #Greenland averaging at least 4°C above normal pic.twitter.com/FFatFKXXfE

— Zack Labe (@ZLabe) April 28, 2016
Read more: http://www.smh.com.au/environment/greenland-ice-sheet-melting-has-started-early-20160429-gohx1z.html#ixzz47FyZK2iu 
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