Today 150 heads of state from around the world are meeting in Paris to take on one of the most pressing issues of our time: climate change.? The meeting marks the 21st Conference of the Parties (COP) to the United Nations Framework Convention on Climate Change (UNFCC) , or COP21. This year presents an historic and unprecedented opportunity to bring the countries and citizens of the world together to decide and embark on new paths to improve the lives of people everywhere by reaching a new universal agreement to protect the planet and its people. .

Speaking at the opening of the conference, UN??Ban Ki-moon told world leaders a political moment like this may not come again: You are here today to write the script for a new future.. We have never faced such a test, he continued. But neither have we encountered such great opportunity. You have the power to secure the well-being of this and succeeding generations.

Ahead of COP21, countries submitted voluntary climate action plans to UNFCCC, the UN entity organizing the conference. These are formally called?, or INDCs, and will form the basis of the agreement expected to be reached in two weeks.

The Secretary-General announced today that more than 180 countries have now submitted their national climate plans which cover close to 100 per cent of global emissions. According to experts, even a 2-degree Celsius rise in temperatures will have serious consequences for food and water security, economic stability and international peace, which is why a universal, meaningful agreement in Paris is crucial, Mr. Ban told the leaders.

Countries have recognized that climate change presents an ever growing threat to development, poverty eradication efforts, and the welfare of their citizens.? The impacts of climate change are already being felt on every continent.? According to the?, the world's greenhouse gas emissions are continuing to increase and on the present path, global temperature rise will far exceed the goal to limit the increase to two degrees Celsius that countries have agreed upon to avoid the most dangerous impacts of climate change.

Last year was the hottest year on record and 14 of the 15 warmest years on record have all occurred in the 21st century. Sea levels continue to rise, Arctic sea ice is retreating, and there are more severe weather events, including?extended droughts and floods.

To see what you can do to make a difference, visit the??to find out what steps you can take in?your everyday life to combat climate change, visit the??to learn more about the negotiation process of a universal binding agreement, or join the civil society Action/2015 movement to make your voice heard.

You can watch COP21 live over the course of the next two weeks here:

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