By Terje Solsvik and Gwladys Fouche
OSLO (Reuters) - The award of the Nobel Peace Prize on Friday has autumnal Oslo turning thoughts back to the Arab Spring, but Africans, from Liberia, or perhaps Sudan, offer a strong challenge in perennial speculation on who will win the global accolade.
With no woman winning the award for seven years, there are a number of strong female contenders widely tipped for 2011.
The head of the Norwegian Nobel Committee, who will announce the winner of the $1.5 million prize at 0900 GMT (5 a.m. EDT), gave little away in an interview with Norway's public broadcaster NRK late on Thursday, though he took care to seem to steer questions away from a single-minded focus on Arab pro-democracy demonstrators.
"There are many other positive developments this year that we have observed in the international community," former prime minister Thorbjoern Jagland said. "I think it is little bizarre that researchers and others have not seen them."
Jagland, whose four fellow panelists are all women, said: "What is important for the Nobel Committee is to tackle the real important forces in the international community that contribute to encouraging societies to go in a positive direction."
For some observers, including Norway's often well-informed TV2, that could point to a woman winner.
Faced with a host of deserving nominations each year to benefit from the bequest left by the Swedish inventor of dynamite, Alfred Nobel, the five Norwegian committee members, appointed by the parliament in Oslo, generally have tended to seek diversity from year to year in the characteristics of the peace prize winner.
TV2's favorite, in a broadcast late on Thursday, was Liberian President Ellen Johnson-Sirleaf, the first elected female head of state in Africa, who is running for re-election next week.
The economic and political empowerment of women, notably in developing countries, is cited by many researchers as a positive factor in reducing conflict and improving prosperity.
"We've looked at who's done the most for peace in the last year and at the fundamental forces developing the world, what's in focus and driving the world in the right direction," Jagland told NRK. "There are quite a few important forces that we've looked at, and one of them we reward."
Several of those nominated for the prize as leading lights in the Egyptian and Tunisian protest movements are women -- Asmaa Mahfouz and Israa Abdel Fatah of Egypt's April 6 Youth Movement Facebook group and Tunisian blogger Lina Ben Mhenni are among nominees who might be part of an Arab Spring award.
But the difficulty of identifying a clear individual, or even formal group, which might receive the prize on behalf of the Arab Spring movements, may discourage the committee -- as might continued uncertainty about the impact of the changes, both in Egypt and Tunisia, as well as in Libya, Syria, Yemen and elsewhere, where bloodshed is continuing.
Egyptian men Ahmed Maher and Google executive Wael Ghonim, arrested for trying to help keep social media alive during the protests that toppled Hosni Mubarak, are also cited among potential laureates. Afghan Sima Samar is another contender, for her efforts to improve women's rights and access to healthcare.
The secession of South Sudan after years of conflict might also be a contender for recognition, though precisely who would be honored is unclear. The arrest this year of the last major war crimes suspects from the fighting in the former Yugoslavia could be reason to honor the court which has tried them.
The list of possible recipients of the committee's annual favor is almost endless, however, ranging from Europeans like former German chancellor Helmut Kohl and the European Union itself to Cuban dissidents and a Vietnamese monk.
It is unlikely, Jagland said, that the choice will prove as controversial as the first two laureates named during his time as chairman of the panel -- Barack Obama, honored in 2009 after less than a year as U.S. president on the strength of promises he made, and last year's winner, jailed Chinese dissident Lu Xiaobo, whose recognition infuriated Beijing.
"This is a very strong Nobel Peace Prize for many people, but it is a consensual one for the international community," Jagland said. "It is not uncontroversial but it will not create as much reaction from one country as it did last year."
Former U.S. president Jimmy Carter, whose work after leaving office in promoting democracy and human rights won him the Peace Prize in 2002, told Reuters on Thursday that Obama still had to fulfill the promises which had earned him the award two years ago. He said that last year's recognition of Lu may well have a positive effect for rights in China, despite the public anger.
As for predicting a winner this year, however, Carter echoed many seasoned Nobel-watchers: "I have no idea," he said.
"I didn't know when I got it."
(Writing by Alastair Macdonald in Oslo; Editing by Michael Roddy)