Science Lecture Series 2016 Earth Transformed

It has been reported that climate change has generated a ‘new normal’ for our weather and our climate. True, but the new reality is less a single new climate than an ever-changing climate driven by the burning of fossil fuels and other human activities. The change is most noticeable at the global scale, but even in the Southwest the change is now firmly upon us in the form of unusually hot and severe drought, looming water shortage, widespread death of trees, unprecedented severe fire risk, dust storms, hotter heat waves and more. Climate change is likely driving the most pervasive and challenging transformations humans have yet faced. People from all walks of life will need to learn early and learn often how to adjust their plans and actions to the ever-changing new normal. Climate adaptation applied in concert with climate mitigation is the challenge of the century.

Climate change as a result of carbon dioxide emissions from industry and power plants (especially coal-fired plants) is a world wide concern. Global strategies are required such as those proposed by the International Energy Association, which states that a minimum of 1/6th of CO2 future emissions must be captured and stored by 2050 to limit rises in average global temperature. Although there are many methods for capturing carbon, the primary barriers are testing them at a large scale, building an infrastructure to support them, and cost. These technologies include everything from injecting CO2 in the ground to recover oil to pumping it deep into the ocean to storing it in deep saline reservoirs to producing soil amendments. In addition to reviewing these technologies, this lecture will discuss methods for reducing carbon emissions by using more alternative energy as well as CO2 uptake by microalgae to produce food and fuel.

Climate change induced impacts on human health are myriad; they range from direct effects, such as heat related mortality during extreme heat events, to indirect effects on infectious disease transmission systems. Predicting the degree of impact climate change will have on a specific health outcome becomes more difficult as the pathways become more indirect. One such example is determining the potential risk of dengue emergence in the U.S.-Mexico border region whereAe. aegypti mosquito populations that transmit the virus are well-established. A suitable natural environment is necessary but not sufficient for virus transmission. Social, economic, and behavioral factors can all enhance or reduce risk. While these factors make predictions difficult, they also suggest a level of control that we as a society have to reduce our risk of negative health outcomes linked to a changing climate. Both top-down and bottom-up actions must be taken now to mitigate current and future health threats.

How can humans thrive within a natural world that holds the ingredients necessary for our survival, but at the same time is threatened by our domination of that world? Sustainability of the goods and services provided by Earth’s ecosystems is dependent on mechanisms of resilience that include maintenance of biotic diversity and avoidance of climatically-controlled ‘tipping points’. This lecture will explore how recent trends in land use and anthropogenic climate warming have exposed vulnerabilities in the mechanisms of ecosystem resilience, and revealed the potential for surprising shifts in the productivity and persistence of ecosystems. Recognition of the interactions between anthropogenic climate forcing and natural climate cycles, and breakthroughs in the fields of genomics and ecosystem modeling, provide opportunities for management of ecosystem resilience. With adequate foresight and focus, humans can learn to navigate toward a more sustainable future.

By the end of the century, the season averaged growing temperature will very likely exceed the highest temperature ever recorded throughout the tropics and subtropics. By 2050, the increase in temperature alone is projected to cause a 20% reduction in the yield of all of the major grains (maize, wheat, rice and soybeans). The breadbasket countries in the midlatitudes will experience marked increases in year-to-year volatility in crop production. Increasing stresses on the major crops due to climate change, coupled with the increasing demand for food due to increasing population and development, present significant challenges to achieving global food security. This seminar explores the likely impact of climate change and volatility on food production and availability in the foreseeable future.

Because it serves as the primary gateway through which the intermediate, deep, and bottom waters of the ocean interact with the atmosphere, the Southern Ocean has a profound influence on the oceanic uptake of anthropogenic carbon and heat. Yet it is the least observed and understood region of the world ocean because of harsh conditions. The oceanographic community is on the cusp of two major advances that have the potential to transform understanding of the ocean’s role in climate. The first is the development of new biogeochemical sensors mounted on autonomous profiling floats that allow sampling of ocean biogeochemistry and acidification in 3-dimensional space. The second is that the climate modeling community finally has the computational resources and physical understanding to develop fully coupled climate models that can represent crucial mesoscale processes in the Southern Ocean. Together with the observations, this new generation of models provides the tools to vastly improve understanding of the ocean’s ability to absorb anthropogenic carbon and heat both today and into the future.