"On the timescale of a decade, climate variations may result from processes internal to the climate system or may be produced by external factors (anthropogenic and natural)," Noel Keenlyside of the Leibniz Institute of Marine Sciences told environmentalresearchweb. "Our approach was to consider both factors. Our study is the second in its kind: in contrast to the first (Smith et al. Science 2007) we take a much simpler approach – using only sea-surface temperature observations – to drive the ocean towards the observed state. This way we are able to partly overcome the difficulty associated with sparse subsurface ocean observations in the past."

Since publication of Keenlyside's paper in Nature, it's received a great deal of attention, from scientists and the media. Although the work may have a particular appeal to climate sceptics, the authors were keen to stress that it does not mean that global warming will stop. "It is very important that policymakers understand that natural variations may in certain periods offset global warming, and that this does not mean anthropogenic global warming does not exist," said Keenlyside. "Decadal fluctuations associated with the Atlantic have large socio-economic impacts, for example Sahel rainfall and hurricane activity. Our results are a first step towards one day predicting these impacts."

Academic commentators from the Realclimate blog, who have some concerns about the team's predictions, have even challenged the scientists from the Leibniz Institute of Marine Sciences and Max Planck Institute for Meteorology to put their money where their mouth is.

The Realclimate team has offered to pay €2500 to the Nature authors if they accept the bet and if their prediction that the average temperature for 2000–2010 is lower than, or equal to, the average temperature for 1994–2004 proves correct. Should temperatures over this period be warmer than for 1994–2004 the Germans must pay the Realclimate bloggers €2500. The same applies for the team's forecast for 2005–2015, although the Realclimate scientists have included a get-out clause for both cases if a volcanic eruption or a meteorite hit causes cooling.

The Realclimate writers say that they're proposing a bet because they were concerned by the global media coverage that made it appear as if a coming pause in global warming was almost a given fact, rather than an experimental forecast. "If different groups of scientists have a public bet running on this, this will signal to the public that this forecast is not a widely supported consensus of the climate science community, in contrast to the IPCC reports," they wrote.

Keenlyside and colleagues have yet to respond to the Realclimate bet or invitation to a guest post – when questioned by environmentalresearchweb Keenlyside said that he had no comment.

This isn't the first time that climate predictions have attracted a wager – climate researcher James Annan has bet two Russian climate sceptics $10,000 that the planet will warm. The three will compare average global surface temperatures between 1998 and 2003 with temperatures from 2012 to 2017. Russian physicists Galina Mashnich and Vladimir Bashkirtsev believe that solar variability is having more of an effect on global temperatures than greenhouse gases and expect the sun to enter a less active phase over the next few decades.

But, apart from attracting media and community attention does setting up bets on climate change play any useful role? Annan has suggested the set-up of a financial-style futures market to allow people to hedge against future risk.

"Betting on sea-level rise would have a very real relevance to Pacific islanders," he told The Guardian. "By betting on rapid sea-level rise, they would either be able to stay in their homes at the cost of losing the bet if sea-level rise was slow, or would win the bet and have money to pay for sea defences or relocation if sea-level rise was rapid."

In the meantime, Keenlyside and colleagues plan to incorporate the increased ocean observations from the last 10 years into their forecast system. "In the long run we believe that this shall lead to improved forecasts," said Keenlyside. "In addition we will work on better understanding the mechanisms for decadal variability in the Atlantic."