Teachable Instant: Targeting Greenhouse Gases

Students consider three numbers: the Obama administration's newly announced target for cutting greenhouse gas emissions; the target scientists advise; and the zero target called for by many conservatives.   


It's all in the numbers. President Obama made a key announcement about climate change on March 31, 2015:  He unveiled the U.S.'s targets for cutting greenhouse gas emissions. These emissions, which come mainly from burning fossil fuels, are causing growing instability in the world's climate, including floods, droughts, rising oceans, and violent weather.

Nations around the world are required to set emissions targets in the coming months as part of UN-sponsored climate talks.  The goal is to arrive at a global plan to combat climate change at a summit in Paris this December. Meanwhile, grassroots climate activists across the U.S. and the world are organizing hard to pressure their governments to take dramatic action.


The target announced by the Obama administration is far below what scientists say is needed.  But many conservatives say we shouldn't even have a target: Senate Majority Leader Mitch McConnell and other Republicans argue that cutting emissions will result in job loss.  Scientists say that not addressing climate change will cause much worse dislocation and loss, especially for low-income people. But many Republicans say they don't believe the scientific evidence.  

So what are these numbers, exactly?

Scientists: Climate scientists say that developed countries like the U.S. need to cut their emissions between 25-50% from their 1990 levels by the year 2025 if we are to avoid catastrophic climate change. It is already too late to prevent some climate disruption, but the extent of that disruption depends on our ability to reduce greenhouse gases now.
Obama administration:  The U.S. announced it would cut emissions by 26-28% from 2005 levels by 2025.  Note that the administration is using the year 2005 as a starting place instead of 1990, which is the base year usually used to set targets. This is important, since emissions were much higher in 2005 than they were in 1990. As one analyst noted, it's like the U.S. is "going on a diet, but we're going to use Thanksgiving as our baseline." If we use the international standard baseline of 1990, then the U.S. is proposing to cut greenhouse gas emissions by only 14-16% from their 1990 levels by the year 2025
Republicans: Senate Majority Leader Mitch McConnell pledged to block the administration's targets. McConnell said the Obama plan "would have a negligible effect on global climate but a profoundly negative impact on countless American families already struggling. The regulation is unfair. It's probably illegal."  Many Republicans advocate for no caps on greenhouse gas emissions.
Ask students: 

  • What do you think this situation requires? 
  • What if any targets should the U.S. set?
  • What action should regular people (like us) take on this issue, based on what we know?



Obama administration's emissions target proposal:
Obama administration's climate plan:
Heritage Foundation editorial:
Senator McConnell editorial:  
News stories on the Obama announcement:
Center for Biological Diversity statement on the Obama announcement:
European Commission Climate Action website:

Photo: Grassroots groups protest at the UN demanding that rich nations step up efforts to reduce greenhouse gas emissions. (C) Mongkhonsavat Luengvorapant/Oxfam