# Presentation: 477277

## Atmospheric Radiation Measurement Climate Research FacilityA National User Facility for the Scientific Community

## Overview

- Background
- ACRF mission
- Sites
- Measurements
- Instruments
- Data flow
- Major field campaigns
- Field campaign proposal process

## BackgroundAtmospheric Radiation Measurement (ARM) Program

- Largest global change research program supported by the U.S. Department of Energy
- Created to improve cloud and radiation physics and cloud simulation capabilities in global climate models
- Provides data products from continuous field measurements to advance global climate models

## BackgroundARM Climate Research Facility (ACRF)

- ARM sites and infrastructure designated as a national user facility
- Unique asset for studying global change to a broader national and international research community
- Significant research capability for the global scientific community

## ACRF Mission

- Provide national and international scientific community with  infrastructure needed for global change research
- Includes study of climate alterations, land productivity, oceans, water cycle, atmospheric chemistry, and ecological systems

## Sites

- Permanent research sites located in Southern Great Plains, North Slope of Alaska, and Tropical Western Pacific
- Mobile Facility provides additional atmospheric measurements anywhere in the world

## SitesSouthern Great Plains

- Largest, most extensive climate research field site in the world
- Made up of Central Facility and 30 smaller facilities, which span more than 143,000 square kilometers
- Chosen for variety of cloud types and surface flux properties; large seasonal variation in temperature and humidity

## SitesNorth Slope of Alaska

- Made up of two instrumented sites at Barrow and Atqasuk
- Serves as focal point for atmospheric and ecological research activity on the North Slope
- Chosen for different climates at high latitudes; planetary heat loss from the poles; and ice sheets that affect solar absorption and sea level

## SitesTropical Western Pacific

- Made up of three instrumented sites at Manus; Nauru Island; and Darwin, Australia
- Chosen for warm sea temperatures; deep frequent atmospheric convection; high rain rates; strong coupling between atmosphere and ocean; and variability associated with El Niño

## SitesARM Mobile Facility

- Addresses science questions beyond those of fixed sites
- Contains similar instruments and data systems as fixed sites
- Provides portability and flexibility
- Designed for campaigns up to 12 months in any environment

## Unmanned Aerospace Vehicle (UAV) Program

- Uses UAV and occupied aircraft to make key climate measurements not available  by other means
- Remote-controlled UAVs fly higher and longer than occupied aircraft
- Long endurance at high altitudes important to studying cloud interactions with solar and thermal radiation to heat or cool the earth

## SitesSite Dedication and Deployment Timeline

- SitesSite Dedication and Deployment Timeline

**·****1992****·****1994**** ****·****1996****·****1998****·****2000****·****2002**** ̇****2004**** ̇**

- Southern Great Plains site dedicationManus site at the Tropical Western Pacific dedication Barrow site at the North Slope of Alaska dedicationNauru site at the Tropical Western Pacific dedication Atqasuk site at the North Slope of Alaska dedicationDarwin site at the Tropical Western Pacific dedicationARM Mobile Facility deployment

## Measurements

- Cloud and radiation measurements gathered from instruments on the ground, attached to aircraft, and placed on ships
- Measurement data stored and distributed via Data Archive
- Data used by scientists to research atmospheric radiation balance and cloud feedback processes critical to understanding global climate change

## Instruments

- Comprehensive set of world-class, unique instruments available to the global scientific community
- Key instruments include one of the few operational Raman lidars in the world; millimeter wavelength cloud radars; radar wind profilers; and total sky imagers
- Recent additions are the microwave radiometer and advanced rotating shadowband spectrometer

## Data

- Collected continually for more than 10 years
- Stored in data files, bundled, and processed into single 24-hour file representing data stream
- Provided through ARM website at no cost (www.archive.arm.gov/cgi-bin/arm-archive)
- Current user community includes 2100 registered users from 9 U.S. agencies, 140 universities, and 44 countries

## Field Campaigns

- Focused short-term research activities targeted to address specific science questions
- Provides supplemental measurements to increase routine data and test and validate new instruments
- Provides extensive field data to be analyzed and applied to improve computer models

## Major Field CampaignsAerosol Field Campaign

- Measured aerosols at Southern Great Plains site
- Improved understanding and model-based representation of aerosol radiative influences
- Used ground and airborne measurements to
- Link chemistry and aerosol radiative properties
- Resolve differences between measurements and models of surface diffuse irradiance

## Major Field CampaignsMixed-Phase Arctic Cloud Experiment

- Measured cloud microphysical properties at North Slope of Alaska
- Used surface and airborne instruments to collect data that
- Document the breadth of cloud and radiative transfer processes in mixed-phase arctic clouds
- Can be used in computer models to simulate the Arctic climate

## Major Field CampaignsMarine Stratus Radiation Aerosol and Drizzle

- Conducted at Point Reyes, California, using ARM Mobile Facility
- Study of air pollution on cloud microphysical, precipitation, and radiative  characteristics of marine stratus
- Will provide unique data set to study aerosols and clouds interactions, and their contributions to radiation budgets

## Major Field CampaignsTropical Warm Pool – International Cloud Experiment

- Conducted at the Tropical Western Pacific site at Darwin, Australia
- Designed to characterize cirrus and upper troposphere, along with convective environment
- Dual focus will result in  data to address important questions related to tropical clouds

## Major Field CampaignsRAdiative Divergence Field Campaign 

- Conducted with ARM Mobile Facility, Geostationary Earth Radiation Budget, and African Monsoon Multidisciplinary Analysis stations in Niamey, Niger, Africa
- First direct, well-sampled measurements of the rate at which tropical clouds and dust in Niamey absorb radiation and heat the atmosphere

## Principal Investigator submits pre-proposal
Pre-proposal screened for feasibility 
Full proposal may be invited
Proposal receives scientific and logistic reviews  
Decision made by U.S. Department of Energy Program Manager

- Pre-proposal screened for feasibility
- Full proposal may be invited
- Proposal receives scientific and logistic reviews
- Decision made by U.S. Department of Energy Program Manager

- Field Campaign Proposal Process