New estimate based on the forthcoming upturn in solar activity and El Niño southern oscillation cycles is expected to silence global warming sceptics
The world faces record-breaking temperatures as the sun’s activity increases, leading the planet to heat up significantly faster than scientists had predicted for the next five years, according to a study.
The hottest year on record was 1998, and the relatively cool years since have led to some global warming sceptics claiming that temperatures have levelled off or started to decline. But new research firmly rejects that argument.
The research, to be published in Geophysical Research Letters, was carried out by Judith Lean, of the US Naval Research Laboratory, and David Rind, of Nasa’s Goddard Institute for Space Studies.
The work is the first to assess the combined impact on global temperature of four factors: human influences such as CO2 and aerosol emissions; heating from the sun; volcanic activity and the El Niño southern oscillation, the phenomenon by which the Pacific Ocean flips between warmer and cooler states every few years.
The analysis shows the relative stability in global temperatures in the last seven years is explained primarily by the decline in incoming sunlight associated with the downward phase of the 11-year solar cycle, together with a lack of strong El Niño events. These trends have masked the warming caused by CO2 and other greenhouse gases.
As solar activity picks up again in the coming years, the research suggests, temperatures will shoot up at 150% of the rate predicted by the UN’s Intergovernmental Panel on Climate Change. Lean and Rind’s research also sheds light on the extreme average temperature in 1998. The paper confirms that the temperature spike that year was caused primarily by a very strong El Niño episode. A future episode could be expected to create a spike of equivalent magnitude on top of an even higher baseline, thus shattering the 1998 record.
The study comes within days of announcements from climatologists that the world is entering a new El Niño warm spell. This suggests that temperature rises in the next year could be even more marked than Lean and Rind’s paper suggests. A particularly hot autumn and winter could add to the pressure on policy makers to reach a meaningful deal at December’s climate-change negotiations in Copenhagen.
Bob Henson, of the National Centre for Atmospheric Research in Colorado, said: “To claim that global temperatures have cooled since 1998 and therefore that man-made climate change isn’t happening is a bit like saying spring has gone away when you have a mild week after a scorching Easter.” Temperature highs and lows
1998
Hottest year of the millennium
Caused by a major El Niño event. The climate phenomenon results from warming of the tropical Pacific and causes heatwaves, droughts and flooding around the world. The 1998 event caused 16% of the world’s coral reefs to die.
1957
Most sunspots in a year since 1778
The sun’s activity waxes and wanes on an 11-year cycle. The late 1950s saw a peak in activity and were relatively warm years for the period.
1601
Coldest year of the millennium
Ash from the huge eruption the previous year of a Peruvian volcano called Huaynaputina blocked out the sun. The volcanic winter caused Russia’s worst famine, with a third of the population dying, and disrupted agriculture from China to France.
G8 must avoid man-made disaster
Europe leads on climate change but must be more ambitious by expanding carbon trading and clean development mechanism reform
The symbolic meeting place of the G8 in L’Aquila is a signal of the world’s solidarity with Italy after the terrible earthquake earlier this year. It is also a unique chance to prevent another disaster – this one man-made. Climate change is happening and it is happening fast. When G8 leaders meet in L’Aquila, a global, wide-ranging and ambitious post 2012 agreement in Copenhagen must be their top priority. An agreement which by respecting science brings real global emission reductions.
Such a deal in Copenhagen will demonstrate that we are serious about tackling the climate challenge. This will stimulate the necessary investments to create a green economy, creating new jobs and driving growth over the next two or three decades. Those who understand this today will be the winners of tomorrow.
The post-crisis economy will be very different from its predecessor. And we will not get the same chance twice. That is why the measures to tackle the economic crisis and fight climate change must be done at the same time. We know that there is ample room for improvement in the energy efficiency of businesses, consumers and the government. In fact, according to the International Energy Agency, 54% of the abatement measures needed to keep to a 2C global warming target could be reached through the introduction of existing energy efficient technologies.
The economic crisis can thus be a trigger for smart climate solutions that also save money and provide better energy security.
We go to L’Aquila with a number of key objectives. We will insist on the need to respect the 2C target. We will reiterate the need for a global goal of achieving at least a 50% reduction of global emissions by 2050. In addition, we will ask all developed countries to reduce emissions by at least 80% in the same period and underpin these efforts through robust and comparable mid-term reductions. A key part of the solution will be financing of the fight against climate change: the EU will come forward with proposals in good time on financing, and is of course ready to play its full part.
Indeed, as the largest contributors to past emissions, we of course agree that the developed countries have a special responsibility to take the lead. But this is not going to be enough. The emerging economies, for example, where growth in emissions is surging, must also join in the effort. We must all do our part, in line with the principle of common but differentiated responsibilities and respective capabilities.
The European Union and its member states are proud of the commitments we have made, to reduce emissions by 20% by 2020, and are ready to go further and reduce them by 30% in the context of an ambitious Copenhagen agreement. We are ready to share our experience, such as on emissions trading, with others. We would like to see an OECD wide emissions trading system by 2015. We would also like to reform and develop the clean development mechanism and thereby bring new investment and new technology to the poorest people on the planet.
We are determined to bring European leadership to bear in facilitating an agreement at Copenhagen of which we can all be proud. There is no alternative. If we fail now, we are breaching the contract that all parents must make with their children: to leave them a better world. Let us turn climate change into a global opportunity in L’Aquila.
• Fredrik Reinfeldt is the prime minister of Sweden, which currently holds the EU presidency. José Manuel Barroso is president of the European commission.