In part 1, we talked about the size of planned offshore wind farms, and potential impacts to fisheries, marine mammals and property values. Now we discuss the cost to build offshore wind farms, the role of subsidies to do so, and how much these projects may or may not reduce US CO2 emissions. Our guests again are Peder Hansen from PH Consulting and Lisa Linowes of Industrial Wind Action.

General readers want straight answers on climate. But climate science is complex and full of nuance. This excites scientists, whose research explores the leading edge. But it makes climate reporting difficult. Journalists must understand the science, then competently simplify it for readers, no easy feat. We'll discuss with two editors: Michael White from Nature, and Justin Worland from Time.

The US natural gas pipeline network carries gas from where it's produced to the many places it's used: power plants, factories and millions of homes. Proponents want more pipelines, to replace more coal here and abroad. Opponents worry about methane leakage and local environmental impacts. We discuss with former Congressman Tim Ryan and Gillian Giannetti from Natural Resources Defense Council.

Climate change is already affecting everyday lives. What are the risks as the globe warms?

Though gas has low carbon emissions it's not carbon free. Will the world use more or less?