World leaders flocked to the Paris climate talks full of proactive words, blustering about an "ambitious and binding" agreement, but it takes more talk to make a difference.

More than 160 countries have already trumpeted how much they are prepared to cut their carbon emissions by 2030, but it is unclear if this will be enough to limit the temperature rise to 2 degrees Celsius above preindustrial levels.

That long-stated goal is still within reach, but only just, and the longer people wait, the more difficult it will be. The world cannot wait much longer.

This year is set to be the hottest on record and 2016 could be even hotter, according to the World Meteorological Organization, warning that inaction on climate change could see temperatures rise by 6 degrees Celsius or more.

Climate change will exacerbate economic, social and political tensions and developing nations will bear the brunt of extreme weather events and food insecurity.

The talks won't be easy. A binding mechanism for tracking progress and a system to toughen targets over time still seem a long way off, and countries are divided on many issues.

Money essentially will be the make-or-break issue. Developing countries want promises that climate funding will be available while developed countries remain reluctant to offer either money or technology.

Much has changed over the past six years since the hugely disappointing Copenhagen talks. While developing economies are generally moving faster than developed, with accelerated industrialization producing more greenhouse gases, one thing remains unchanged: developed countries have been historically main contributors to the current global warming.

Countries, in whatever stage of development, must find their own way of making their due contribution to global warming control. China has announced a cap on its emissions by around 2030, while the United States has made pledge of emission cuts of 26 percent to 28 percent below the 2005 levels, typical of the contrast between what is expected from the developed and developing worlds.

Most importantly, countries must walk their talk. Rich countries have pledged to give poor nations 100 billion U.S. dollars each year until 2020 to help them reduce emissions and adapt to climate change. Currently, they are giving just over half that amount.

It will be difficult to effect positive change without binding rules. Only by pooling wisdom for the common good and being more flexible in negotiations with a long-term view can the future of the human planet be assured.