The potential for Dr. Hansen and our group to communicate with decision makers and the public depends on maintaining our high scientific reputation and productivity. That is one reason it is important for us to continue to be at the forefront of climate research.
However, there is a more fundamental reason: good policymaking depends on a good realistic understanding of the science. This is illustrated well by current paper (Assessing “dangerous climate change”: Required reduction of carbon emissions to protect young people, future generations and nature), in which we make a persuasive case that the popular target of limiting CO2 emissions to 1000 GtC (fossil fuel emissions through 2012 are 370 GtC) would actually be a prescription for disaster. Clearly this issue needs to be understood soon, before reality makes the larger emissions inevitable.
One of the strengths of Dr. Hansen’s research has been an ability to recognize the significance of new research opportunities when they arise and move quickly to interpret their significance. Therefore it is better not to confine planned research too specifically. However, the research areas that the team intends to focus on are as follows.
Data on Ongoing Climate Variability and Change
Analysis of global temperature change by the Climate Science, Awareness and Solutions team, updated monthly, is recognized as among the best analyses of ongoing climate change. It has led to significant conclusions, e.g., about the degree to which climate extremes can be attributed to global warming. Our work is recognized for having clear illustrations that can be readily understood by the media and public. We intend to extend this type of analysis to the water cycle, including the analysis of precipitation changes as required to define the changing occurrence of droughts and heavy floods.
Global Climate Forcings and Planetary Energy Balance
Earth’s energy balance is the fundamental indicator of where global climate is headed as well as what is needed to stabilize climate. Our group is recognized as leaders in defining climate forcings, how they are changing, and the equivalence and tradeoffs among different forcings (greenhouse gases, aerosols, etc.), as is required for making good climate policy. By combining data on changing climate forcing with the best empirical data on Earth’s energy balance, obtained via continued collaboration with oceanographer Karina von Schuckmann in France and satellite-derived ice mass data, we can assess progress or lack thereof regarding the changes needed to stabilize Earth’s energy balance and climate.
Earth’s Climate History and Climate Sensitivity
The most reliable and quantitative guide to how the Earth will respond to human-made climate forcings over the long run is how Earth responded in the past to natural changes of its “boundary conditions,” including changes of atmospheric composition and planetary surface properties. We have demonstrated an ability to work with the paleoclimate research community and identify information needed to understand the implications of different levels of human-made atmospheric and environmental changes.
Climate models, used with discretion, are a useful complement to knowledge gained from global observations of ongoing changes of climate forcings and climate diagnostic quantities (temperature, precipitation, etc.) and from analysis of Earth’s paleoclimate history. We prefer relatively coarse resolution models that can be run for the long periods needed to understand climate as opposed to weather variations.
Energy Choices and CO2 Emissions
Because fossil fuels supply over 80% of global energy, it is vital to convey the urgent need to transform world energy and fossil fuel resource data as well as projections of future energy supply. We have published several high-profile peer-reviewed papers analyzing the climate implications of shifting energy choices and outlining relevant policy options. We intend to continue research into this fundamental topic in cooperation with external colleagues with technical expertise that complements our own.