with Jonathan Foley
Reducing sources are the most important things to do
- Electricity Production ≈ 25%
- Food, Agriculture, Land use ≈ 24%
- Industry ≈ 21%
- Transportation ≈ 14%
- Buildings ≈ 6%
- Other, Misc ≈ 10%
Electricity: coal power is the worst...
food and electricty are equally important to do something about
buidlings CAUSE 6% but they then are interconnected with electricity grid, land use, transportation, etc.
The rest of "other" is everything else, but its yet more related to energy, gas leaks, etc.
5 things cause 90% of climate change GHGs
Each sector can be treated on its own...
Electricity: 25% of GHGs the production of energy from burning fossil fuels generates the GHGs
we send the electricity to buildings and industry
focus on efficiency and then shifting production to renewables, with this is the requirement of remaking the grid
Food
food miles isn't really important. the big issues are deforestation, methane from animals, NOx from too much fertilization
same, efficiencies are important, specifically FOOD WASTE. 1/3 of food is just thrown away. Food waste in developing places, the problem is on getting the food to people, in US, etc. its waste at the consumer level
meat based diets are worst
stop deforestation
improve agricultural practices on all the land we are already farming.
regenerative agriculture > can also be sinks?
food solutions: 
Industry
high temperative, energy intensive processes – steel, cement, chemicals, plastics...
plastic is more of an environmental problem, less a climate problem
most importantly, we just need to swap CFCs and HFCs for better refridgerants.
how is waste a better resource? instead of just waste?
Transporation
10 of 14 is roads, 2% is flying... everything else — boats, trains, is 2%... so most importantly is reducing road mileage.
1 gallon of gas is 20lbs of CO2
Fuel efficiency... electric over gas... anything to reduce gas
even better, replace road transport with anything else that doesn't use fuel — bikes, walking, video conferencing, etc.
Buildings
Residential building use more, emit more than anything else. Hot water, boilers, furnaces. Leakage in AC and appliance refrigerants
heating in your building might be more than your car?
massive efficiency improvements required, non fossil fuel energy sources for everything... address refrigerants
Other, Everything else...
mostly flare off gas, leaking natural gas pipelines, etc. this is super low hanging fruit.
to wrap... 
To Do
Start with efficiency, then switch to the low carbon or no carbon sources/ideas
plenty of options, plenty of opportunity, plenty of job creation and new business space