AMF2 Baseline Instruments
Instrumentation for the AMF2 is, with a few notable exceptions, the same as used by the AMF1. Because shipboard deployments of the AMF2 are encouraged, the baseline suite of instruments is marine focused and will generally include:
Atmospheric Profiling
Clouds
- Micropulse Lidar (MPL)
- Microwave Radiometer (MWR)
- Narrow Field of View (NFOV)
- Total Sky Imager (TSI)
- Vaisala Ceilometer (VCEIL)
- W-band (95 GHz) ARM Cloud Radar (WACR)
This instrument is currently being modified to enable scanning (scanning WACR or SWACR). The SWACR will be a normal part of AMF2 deployments. - Wind Profiler
Land-based deployments will include a standard 915 MHz wind profiler. Operation of a standard RWP on a ship is not only difficult but expensive to stabilize and is currently not included for ship-based deployments.
Radiometers
- Marine Atmospheric Emitted Radiation (MAERI)
The MAERI, a marine version of the land-based Atmospheric Emitted Radiance Interferometer (AERI), is used to make measurements of both atmospheric and sea surface radiation. These measurements evaluate sea surface temperature and emissivity, as well as atmospheric radiances. - Multifilter Rotating Shadowband Radiometer (MFRSR)
- Radiometric Instrument Systems
- Upwelling Radiation (GNDRAD)
For GNDRAD data (longwave, shortwave, and infrared skin temperature) to be useful, these measurements will be taken from a boom projecting forward, mounted as far forward on a ship as possible. - Downwelling Radiation (SKYRAD)
The three radiometers that make up this system (broadband shortwave, longwave, and ultraviolet) make diffuse measurements using a three-component solar tracker. For ship-based deployments these trackers will be mounted on a stabilized platform, which will be able to respond in real time to changes in the ship's location and attitude (pitch and roll).
- Upwelling Radiation (GNDRAD)
- Rotating Shadowband Radiometer (RSR)
The RSR is a test instrument that holds promise for relaxing some stability requirements of a ship-based deployment, potentially reducing the need for expensive, complex sun trackers for future applications. In the near term, both sets of instruments (SKYRAD and RSR) will be operated for continuity with existing ACRF datastreams.
Surface Meteorology
- Meteorological Instrumentation at AMF (MET)
To provide accurate wind measurements, the roll, pitch, and yaw rotations (as well as ship speed and direction) will be incorporated into the datastream and will be used in a post-processing step approximately once per hour. In addition, this new ship disposition datastream will be separately maintained and available to users as an AMF2 data product. Optical sensors will measure precipitation for the AMF2, but unlike the AMF1 a tipping bucket, will not be used. The anemometers used on the AMF2 are 2D heated ultrasonics. - Bulk Aerodynamic Fluxes (BAF)
The BAF is a new ACRF measurement (although similar calculations are made in the BAEBBR VAP to correct EBBR calculations when the Bowen ratio is near -1). Aerodynamic fluxes will be measured using wind speed, wind direction, and temperature data from the MET tower, but at a height appropriate for the bulk aerodynamic calculations. Measurements of the ocean current speed and direction—for proper calculation of the momentum flux and surface roughness—will be supplied by an acoustic Doppler current profiler (ADCP). Sea surface temperature and downwelling radiation data are also necessary. Because merging of multiple datastreams is required for the BAF calculations, these fluxes will be calculated in a post-processing step. Land-based deployments will incorporate a standard ECOR system for flux measurements. - Ocean Meteorology
Ocean meteorology instruments will measure water temperature and salinity in the mixed layer at the ocean surface. - Sea State
A digital camera will regularly scan 360° to provide visual evidence as to the sea state (e.g., wave height, white caps, water spouts). - Acoustic Doppler Current Profiler (ADCP)
An ADCP provides 2D or 3D water currents required for the BAF measurements.
