Atmosphere and Climate

Air pollution exposure in the United States is worsening due to changes in the environment and extreme natural events, such as wildfires and volcanic eruptions.

The accelerating impact of climate-driven perturbations have led to unprecedented levels of mass-mortality events worldwide. Given the impacts that these events could have on ecological function and the provisioning of ecosystem services, understanding the mechanisms underpinning ecological stability in response to climate change is among the most urgent conservation challenges of our time.

Sea-level rise and storms cause major changes on coastal landscapes, including shifts in elevation, ecosystem type (for example, dunes and tidal wetlands), soils, and plant communities. Because these changes can have impacts on human communities, the local economy, and ecosystems, understanding how, when, and why these changes occur can be important for informing policy and natural resource manage

A revolution is underway in seismology that transforms fiber-optic cables into arrays of thousands of seismic sensors. Compared to the traditional monitoring networks using inertial seismometers, the fiber-optic approach can increase the spatial data density by orders of magnitude and enable data processing methodologies that require a high-fidelity wavefield. The Working Group aims to advance the

Despite the critical services freshwater systems provide, freshwater biodiversity has been vastly under-studied compared to terrestrial and marine biomes. In fact, systematic compilations of freshwater zooplankton are surprisingly rare despite the critical roles zooplankton play in regulating and supporting ecosystem services, serving as key indicator species, and consequently, influencing emergen

The pervasive nature of insect species’ declines has led to the specter of an “Insect Armageddon” in the popular press. Insect-derived ecosystem services are valued at > $57 billion in the U.S. and thus the loss of insects has the potential to fundamentally disrupt natural and economic systems.The causes of insect declines have been linked to changes in climate, land use and pesticide use, but the

Increasing wildfire activity in much of North America is having severe impacts on society and ecosystems. Climate change is a key driver of changing fire regimes across North America, with varying expressions across the continent. Modern fire records, while useful, are too short to fully characterize the complex patterns and non-linear dynamics of fire-climate relationships that are required to un

Climate change is expected to have significant effects on the phenology of vectors of arthropod-borne diseases, particularly mosquitoes. However, forecasting the direction and magnitude of future phenological shifts requires a more detailed understanding of the climate drivers of mosquito phenology. Addressing this knowledge gap is particularly salient for mosquitoes, as they have the potential to

Biological nitrogen fixation (BNF) is a critical biogeochemical process that converts inert atmospheric N2 gas into biologically usable forms of the essential nutrient nitrogen. A variety of free-living and symbiotic organisms carry out BNF, and in most regions worldwide, BNF is the largest source of nitrogen that fuels terrestrial ecosystems. As a result, BNF has far reaching effects on ecosystem

This proposal brings together biologists and geoscientists to evaluate the evolution of stress tolerance and adaptation to extreme environments in plants. Stress tolerance has been studied mainly from a physiological perspective using laboratory and field experiments. In contrast, this project will take a combined environmental and evolutionary perspective using national public databases and a “bi

Regional- to continental-scale paleoclimate syntheses of temperature and hydroclimate in North America are essential for understanding long-term spatiotemporal variability in climate, and for properly assessing risk on decadal and longer timescales. However, existing syntheses rely almost exclusively on tree-ring records, which are known to underestimate low-frequency variability and rarely extend

Advancing our mechanistic understanding of ecosystem responses to climate change is critical to improve ecological theories, develop predictive models to simulate ecosystem processes, and inform sound policies to manage ecosystems and human activities. Manipulation of temperature in the field, or the “ecosystem warming experiment,” has proved to be a powerful tool to understand ecosystem responses