Here is the multi $trillion question: "How do we proceed so that the data so far collected can help us to mitigate the effects of climate change?" The answer is both very simple and extremely complicated.

At the science level, the data show us that greenhouse gases and associated feedback mechanisms are now responsible for reversing what would be a natural cooling trend and adding a heating component that is raising the temperature of the atmosphere, land, and ocean. These same data indicate clearly that continuing this trend has the potential to create very damaging impacts on civil society and human health and well-being, as well as damaging the economic infrastructure if left unattended. We also know that there are points along the trend that create an inevitable level of impact that cannot be turned around for a very long period time. These include sea level rise sufficient to destroy large segments of the coastal infrastructure; loss of freshwater supplies due to inundation of freshwater aquifers and melting mountain ice caps; disease vector insects and pest insects will increase their invasion across previous cold temperature barriers to dispersion, and much more. Once these events have occurred they cannot easily be reversed, nor is it easy to adapt to them.

Science can also predict what the consequences of climate change related decisions will be. In fact, we know that in the recent geological past (125,000-115,000 years ago) temperatures about the same as today's or a little warmer caused 6-9m sea level rises. The next closest analogue of today's CO₂ levels had temperatures on the order of 3-4⁰C higher than we are experiencing now, implying that with enough time for the feedbacks to mature, we would also experience that much warming and sea level rises of up to 20m or more. The science also tells us that the time frame for recovery, once we reach given sea level increases, is on the order of millennia - assuming we reduce the greenhouse gases to pre-industrial levels.

At the engineering level, the mechanisms to reverse this global warming are also at hand. The data show us that the main sources of the greenhouse gases that are initiating the warming are the use of fossil fuels, inappropriate agricultural practices, deforestation, energy inefficiency, and carbon emitting industrial processes such as smelting and concrete manufacturing. We have the mechanisms to make the transition to carbon-free sources of energy including nuclear, wind, water, solar and newish technologies such as fuel cells on a commercial scale, and battery storage improvements. Engineering techniques can be combined with agricultural practices to reduce greenhouse gas emissions and save money. No till planting, for example, saves time and money as well as being helpful for reducing greenhouse gases. Wasteful deforestation practices as well as substitution of other products for wood construction and burning is also well within known engineering competence. Energy saving and efficiency practices are also known and can be implemented using known practices. Concrete can be produced without using coke and can also be used as a repository for captured CO₂. Smelting processes can be done with electrical power, which, if from a carbon-free source, eliminates almost all the CO₂ release. The combination of these things will eliminate excess greenhouse gas emissions. I must comment that removal of CO₂ from the atmosphere is one area of engineering and technology where our capacity is currently not up to the task, so we need more research and development in carbon removal from the atmosphere.

We know enough to be able to define both the nature of the problem, the underlying causes, the potential danger, and with a little more research and development in CO₂ capture from the atmosphere, we know how to fix it.

Now what? The scope of the problem is global, so the solutions must be global as well. Is there an official role for science and technology beyond this stage? We, the scientists and engineers, understand what needs to be done. But are we in a position to undertake the task of "doing it?" No organization has been officially tasked with solving global warming. The United Nations established The United Nations Framework Convention on Climate Change (UNFCCC) whose "main aim is the stabilization of greenhouse gas concentrations in the atmosphere at a level that would prevent dangerous anthropogenic interferences with the climate system." The framework sets no binding limits on greenhouse gas emissions for individual countries and contains no enforcement mechanisms. As such it is currently a failure, we are already beyond the threshold of safe greenhouse gas levels. The IPCC is in an advisory role. The Paris Agreement is voluntary. Everything else is fundamentally voluntary and self-imposed at levels ranging from regional and national to personal. It may well be that a voluntary global initiative will take hold sufficiently to solve the problem, but that is not obvious yet. There are now literally dozens of sources for information on what to do, suggestions for programs to undertake, methods of adapting to impacts, and even geo-engineering solutions that could form a temporary stop-gap for correcting delays in implementation that are too prolonged.

As a general question to those who feel a solution to global warming and its attendant climate change impacts is needed, what further roles should we as scientists and engineers take in implementing the solutions? How would we undertake them?