I am very excited about my first trip to Brazil, partly because I can finally practice the Portuguese I have been studying for the past few months.

Of course, Brazil is more than just the language. To me, it is the country of samba, soccer and Corcovado, with its giant statue of Jesus. A land of abundant resources, fertile land and the Amazon; a land of the future as Austrian author Stefan Zweig called it.

The South American nation, the fifth largest country in the world, has much of what the rest of the world needs for a sustainable future.

That is probably why the leaders of more than 130 countries will gather in Rio de Janeiro for the Rio+20, the short name for the UN Conference on Sustainable Development, to shape ways to reduce poverty, advance social equity and ensure environmental protection to create to a safer, cleaner, greener and fairer world.

More than 50,000 people from around the world are expected to flood into Rio in the coming days, with world leaders, along with thousands of participants from governments, the private sector, NGOs and other groups attending hundreds of events.

Rio+20 is taking place 20 years after the Earth Summit held in Rio in 1992, where landmark global agreements on climate change, forests and biodiversity were produced.

But these agreements have not achieved their desired results. Over the past few years, world leaders at climate change talks have failed to show a commitment strong enough to avoid the possible worst-case scenario.

That is discouraging and expectations for Rio+20 have fallen even further with the announcement that US President Barack Obama has decided not to attend the summit despite the repeated urgings of UN Secretary-General Ban Ki-moon. Obama will send Secretary of State Hillary Clinton instead.

In the US, such an arrangement has let down many environmentalists and people like Jeffrey Sachs, the director of The Earth Institute at Columbia University and a special advisor to the UN Secretary-General on Millennium Development Goals. Sachs predicted in a seminar in New York on Monday that neither US presidential candidates, Obama or Mitt Romney, are likely to mention the word "climate change" in the coming four months leading up to the November election. In Sachs' eyes, any serious talk among grown-ups has become impossible among politicians in the United States today.

While the lack of clear and strong leadership from the US is indeed a blow to the global endeavor, leaders of the more than 130 countries should be commended for attending the summit.

Yes, the challenges are huge and many. As reported, countries are still haggling over the draft of the summit outcome document known as "The Future We Want". Yet the world will move forward when leaders show their willingness to talk about the issues and share best practices in developing a green economy, instead of shying away from the challenges.

The official discussions will focus on how to build a green economy to achieve sustainable development and lift people out of poverty, and how to improve international coordination for sustainable development.

This is especially necessary given the global economic recession. The possible fallout from the Greek election this coming Sunday, in which Greece may leave the eurozone, has probably already caused many world leaders sleepless nights.

Meanwhile, developing countries, China included, still face huge pressure to reduce poverty and improve the livelihoods of its people. Following a green path of development might mean slower growth and more expensive growth given all the strict environmental standards to be enforced. Unfortunately that seems to be a necessity for the world today.

The developed nations have left a heavy historical burden on the planet. The developing nations no longer have the luxury of repeating that kind of mistake.

After all, we don't want to leave our children and grandchildren in a land with no future.

The author, based in New York, is Deputy Editor of China Daily USA. E-mail: chenweihua@chinadaily.com.cn

(China Daily 06/15/2012 page8)