The Washington Post provides a good introduction to these strategic moves :
The commitments by the three countries came in different forms and units, ranging from forest hectares to renewable energy gigawatts — but collectively appeared to represent a major step toward addressing climate change and cleaning global energy systems.
On Brazil and the United States, The Guardian reported :
Barack Obama and Dilma Rousseff put climate change at the top of their agenda at their bilateral meeting on Tuesday, with the US and Brazil agreeing to obtain up to 20% of their electricity from renewable power by 2030.
Brazil also committed to restoring up to 12m hectares of forest – an area about the size of England or Pennsylvania – in another attempt to reduce the carbon pollution that causes climate change.
(…) The pledge will require the US to triple its production of wind and solar power and other renewable energies. Brazil will need to double its production of clean energy. The figures do not include hydro power.
On China, The Climate Group noted :
China will cut its CO2 emissions per unit of GDP by 60-65% from 2005 level by 2030, aiming to increase non-fossil fuel sources in primary energy consumption to about 20% by the same date. However, China “will work hard” to peak its CO2 emissions before 2030, Prime Minister Li Keqiang revealed.
The commitment comes in the much-awaited Intended Nationally Determined Contribution (INDC) that China presented today ahead of the UN climate talks in Paris (COP21), where a global climate deal is expected to be agreed which will come into force by 2025.
On most commitments I believe that these countries will actually outperform these goals as all three are working hard on renewable energies. Additionally, as climate change gets more pressing, these targets will be re-evaluated to become even more ambitious. Another reason for that is how renewables are getting cheaper and better each month.
What do YOU think ?