Centennial Tutorials (Fall Meeting 2018)

Understanding a new or different field of study or a new issue or challenge provides an opportunity not only for learning: it can also spark new ideas, generate a new way to approach a problem, or even lead to unexpected collaborations. The new Tutorial Talks introduced for AGU Fall Meeting 2018 were inspired by the launch of AGU’s Centennial.

Integrating Public Health and Well-Being into the Geosciences

The opportunities are profound and yet the obstacles seem overwhelming—huge datasets that span many parts of the globe exists in the health sciences and the earth system sciences, with the potential for vastly improving global public health, yet they exist largely isolated from one another. The new field of GeoHealth is attempting to bridge the divide between the health sciences and the geosciences by building research and communication connections between these fields, demystifying the often disparate ways that these fields develop research infrastructure, sample their “subjects,” store and analyze data, and finally communicate their research findings to the greater public. This tutorial will demystify some of the human health terminology and data structures and discuss several ways that researchers are working across the GeoHealth divide, including utilizing satellite and drone-based platforms to understand and reduce disease transmission, working with communities and citizen scientists to co-discover pollution exposure risks, and utilizing climate change and future climate models to downscale environmental health risk maps for municipal policy-makers.

It's All Good: The Reciprocity of Diversity in STEM Disciplines

Diversity is a vital priority that promotes innovation and strengthens a community's resiliency. The lack of diversity in science, technology, engineering, and mathematics (STEM) disciplines is not a new development and the geosciences continue to lag other STEM disciplines in this area. Many current and historical geoscience education funding efforts have focused on increasing the numbers of participants from under-involved groups in the geosciences but often have lacked the equally important focus of developing appropriate climates for retention. Expansion of scientific knowledge and preparation of the future professional geoscience workforce includes increasing the pool of educated, well-qualified individuals, but it should also include efforts to develop and sustain supportive learning, research and professional environments to retain said individuals. To this effect, social science expertise is critical and should be enthusiastically welcomed to help broaden the understanding of diversity, equity and inclusion in the geosciences.

High-Energy Radiation from Thunderstorms

Thundercloud regions with the highest electric fields can glow continuously with gamma radiation; lightning leaders produce bursts of x-rays; and when the two meet, enormously bright radiation bursts called Terrestrial Gamma-ray Flashes (TGFs) can be formed, either beamed upwards into space or downwards toward the ground.  In the heart of these extraordinary events, which accompany a small fraction of lightning flashes, the radiation dose may be high enough to endanger people aboard aircraft on rare occasions.  TGFs have recently been shown to produce a flood of neutrons and radioactive nuclei as well, and to launch beams of electrons and positrons into Earth's magnetosphere.  I will survey the history, physics, status, and future of this unusual field of study, which brings together electrical engineers, meteorologists, and astrophysicists.

Aerosol Mixing State: Metrics, Measurements, Modeling

Despite decades of study, aerosol-cloud interactions remain the largest uncertainty in climate projections, partly due to the chemical and physical complexity of aerosols in the atmosphere, and how we describe, measure and model it. Atmospheric aerosols are complex mixtures of different chemical species, and individual particles exist in many different shapes and morphologies. Together these characteristics are called the aerosol mixing state. This tutorial begins with an overview of the main aerosol types and their relevance in the atmospheric system. We will synthesize our knowledge of aerosol mixing state’s fundamental impact on climate-relevant properties, such as cloud condensation, ice nuclei concentration and aerosol optical properties. Findings are presented within a framework that defines aerosol mixing state along with appropriate mixing state metrics to quantify it. We then give an overview of measurement techniques to probe aerosol mixing state and discuss how aerosol mixing state is represented in atmospheric models at different scales. Future research directions are identified, with a focus on the need for integrating mixing state measurements and modeling. Taken together, this tutorial communicates how aerosol mixing state relates to climate-relevant aerosol properties and why improved understanding of these topics is needed to reduce uncertainties related to aerosol-cloud interactions.

Science of a Rapidly Changing Arctic System

The Arctic system is changing rapidly. Melting land and sea ice, thawing permafrost, atmospheric extremes, warming oceans, and terrestrial landscape changes have already created a new Arctic “normal”. Dramatic future changes are expected, with significant consequences, ranging from sea level rise to ecosystem disruption, exacerbated greenhouse gas emissions to changing weather patterns. Based on an NSF Arctic System Science Workshop (April 2018) - gathering international scientists with expertise including land ice, sea ice, atmosphere, ocean, and terrestrial processes - this tutorial will overview the connected physical systems of the Arctic, discuss its recent evolution as the most rapidly warming region on the planet, and highlight the next frontier in Arctic system science. The future of Arctic system science includes developing new partnerships across observational and modeling efforts, focusing on interdisciplinary boundary regions between Arctic system components, exploring the feedbacks of increasingly common extreme events, and preparing research to understand the impacts of moving from an ice-dominated system to a water-dominated system. We need all hands on-deck to understand the consequences of warming across this difficult-to-study region. This tutorial will bring scientists, stakeholders, and the interested public up to date on Arctic system science and the challenges and opportunities ahead.