The BEACHON Project

What is BEACHON?

Bio-hydro-atmosphere interactions of Energy,
Aerosols, Carbon, H2O,
Organics & Nitrogen

The BEACHON Project is a study of the impact of biogenic aerosols on clouds and precipitation, especially focused on the links between carbon, nitrogen and water cycles.

Overall Goal:

Characterize and understand interactions between biogeochemical and water cycles across scales and their response to climate and land-use change

Motivations:

• The earth system is changing

• Need to predict changes and their impacts on time scales of months to decades

• Requires understanding of the coupling between energy, water, carbon and other biogeochemical cycles in a multi-scale framework (graphic above & right).

• Requires modeling, observations and process studies

• Particularly important for water-limited landscapes

The importance of Bio-hydro-atmosphere interactions of Energy, Aerosols, Carbon, H₂O, Organics and Nitrogen:

Ecosystem-biogeochemistry-climate interactions

• Uptake and emission of carbon
• Coupling with local water processes
• Coupling with nitrogen

Interactions of the water cycle with climate and weather

• Large-scale analysis of water cycle
• Diurnal cycle, precipitation climatology
• Clouds and land-air interactions, hydrology

The role of aerosols in climate and weather

• Feedbacks among soil-dust, biogenic aerosols and terrestrial ecosystems
• Secondary organic aerosols
• Indirect effects of aerosols

Key Questions:

WCRP-GEWEX key questions:

• Are the earth’s energy budget and water cycle changing? Is the water cycle accelerating?
• Can we predict these changes for up to seasonal to interannual timeframes?

IGBP-iLEAPS key questions:

• How do interacting physical, chemical and biological processes transport and transform energy, momentum and matter through the land-atmosphere
• How did the terrestrial-ecosystem/atmosphere system function under pre-industrial conditions, and how are human activities influencing it?

Objectives:

A. Process studies across scales using observations & models:

• CO₂ exchange
• VOC & bio-particle emissions
• CCN & IN
• Cloud interactions
• Impact of clouds on environment
• Soil moisture
• Transpiration & energy flux

B. Improve parameterizations

C. Simulation influence of climate & land use change on coupled feedback system

D. Assess model with field observations

Approach:

BEACHON will focus on water-limited ecosystems in western U.S. and compare and contrast with other ecosystems.

Water-limited ecosystems:

• Greatest response to changes in precipitation
• Cover half of the earth’s surface
• Fast growing population centers

Tropical rainforest ecosystems:

• High annual precipitation but often have water-limited dry season
• High annual biosphere-atmosphere exchange rates
• High rates of landcover change