Leaders from across the scientific community, business, academia, government, the military and more agree that climate change is a serious issue that threatens human civilization. We've posted a few of their comments below - feel free to send us more by posting on our Facebook Wall.

Nancy Pelosi and Newt Gingrich

Current and former Speakers of the House - one a Republican, one a Democrat - discuss the importance of addressing climate change.

US Military

In 2008, approximately $20 billion of Department of Defense budget was spent on energy... every $10 increase in the price of a barrel of oil costs the Department $1.3 billion. This is just one of several reasons that the US Military is seeking solutions to climate change.

Just this July, the CNA Military Advisory Board published a report in which they found that “Continued over-reliance on fossil fuels will increase the risks to America’s future economic prosperity and will thereby diminish the military’s ability to meet the security challenges of the rapidly changing global strategic environment.”

According to an article about climate change and national security in 2009, the National Intelligence Council "concluded that climate change by itself would have significant geopolitical impacts around the world and would contribute to a host of problems, including poverty, environmental degradation and the weakening of national governments." 

The article also quotes a report from Gen. Anthony C. Zinni, a retired Marine and the former head of the Central Command, prepared as a member of a military advisory board on energy and climate at CNA, a private group that does research for the Navy. “We will pay to reduce greenhouse gas emissions today, and we’ll have to take an economic hit of some kind. Or we will pay the price later in military terms. And that will involve human lives.”

President Hu Jintao of China

In 2009, President Hu Jintao of China delivered a compelling speech to the United Nations on climate change and his country's commitment to action. Here's how it began:

"Global climate change has a profound impact on the survival and development of mankind. It is a major challenge facing all countries."

China is one of the world's fastest growing countries and the leading producer of greenhouse gases. It is reassuring to see China make a strong commitment to addressing climate change for both the present and posterity. 

Russian President Medvedev

When it comes to extreme weather, this past summer was a devastating one for Russia. In the wake of wildfires, extreme heat, and drought - President Medvedev has made a strong statement about climate change and the need for action:

"What is happening right now in our central regions is evidence of this global climate change, because we have never in our history faced such weather conditions in the past. This means that we need to change the way we work, change the methods that we used in the past.

We are in the middle of an unprecedented heat wave…We have never had such record high temperatures before. Frankly what is going on with the world's climate at the moment should incite us all (I mean world leaders and heads of public organizations) to make a more strenuous effort to fight global climate change."

James Hansen

The head of the NASA Goddard Institute for Space Studies and a world-renowned climatologist discusses his career of climate research in this New York Times interview.

Corporate Leadership

Many companies have taken the lead on curbing climate change. Just a few leaders include Hewlett-Packard, Starbucks, Nike and Dell, and you can check out a list of the top 500 green businesses via Newsweek's latest green company rankings.