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Air Sea Interaction Tower
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The Air Sea Interaction Tower (ASIT) is located at Lat:41.325040N, Long:70.566678W, 2800m or 1.5NM, from the southern coast of Martha's Vineyard. Underwater instruments are located on a steel beam, mounted 4m below msl and on the leg of the tower, 2m agl. Air side instruments are mounted at varying heights on and above the tower's mezzanine deck, between 13m asl and 23m asl. Data collection on the ASIT began on August 5, 2004.


Data Headers
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Column 	Name												(unit)
1	Timestamp		Start time of averaged data						(UTC)
2	wspd_u_mean		Average u wind speed over the recording period				(m/s)
3	wspd_u_std		Standard deviation of u wind speed over the recording period		(m/s)
4	wspd_v_mean		Average v wind speed over the recording period				(m/s)
5	wspd_v_std		Standard deviation of v wind speed over the recording period		(m/s)
6	air_temp_mean		Average air temperature over the recording period			(deg C)
7	air_temp_std		Standard deviation of air temperature over the recording period		(deg C)	
8	air_rh_mean		Average relative humidity over the recording period			(deg C)
9	air_rh_std		Standard deviation of relative humidity over the recording period	(deg C)
10	air_press_mean		Average air pressure over the recording period				(mbar)	
11	air_press_std		Standard deviation of air pressure over the recording period		(mbar)		
12	water_temp_mean		Average water temperature over the recording period			(deg C)	
13	water_temp_std		Standard deviation of water temperature over the recording period	(deg C)	
14	water_salinity_mean	Average water salinity over the recording period			(PPT)	
15	water_salinity_std	Standard deviation of water salinity over the recording period		(PPT)	
16	water_conductivity_mean	Average water conductivity over the recording period			(S/m)	
17	water_conductivity_std	Standard deviation of water conductivity over the recording period	(S/m)


Data Description
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Wind:
A composite wind record (wspd_u,wspd_v in meteorological convention, i.e. the direction the wind is coming from) is formed from a series of research grade Gill Sonic Anemometers, mounted at 18.4m asl, augmented by a windsensor P2546A cup anemometer and NRG 200p wind vane, mounted at 26 and 23 m asl respectively.  All data have been normalized to a standard 10m height following the methods of Liu et al. (1979), and quality controlled through a series of range tests following the standards of NDBC (2009) and manually reviewed to omit periods of faulty data. The wind sensors are owned by users Jim Edson and Anthony Kirincich, and operated by MVCO.

Air Pressure, Temperature, Relative Humidity:
The available Air Pressure, Temperature, and Relative Humidity data have been collected using a series of Vaisala PTU307 sensors, mounted on a Rohn strut extending above the deck level of the tower, at 18m asl. These data have been collected since 2004. Sensors are swapped out on failure. The data have been quality controlled through a series of range tests and statistical tests following the standards of NDBC (2009) and manually reviewed to omit periods of faulty data. Sensors are owned by user Jim Edson and MVCO, and operated by MVCO. 

Water Temperature, Salinity, and Conductivity:
The available Water Temperature, Salinity, and Conductivity data have been collected by a Seabird 37 CTD mounted 4m bsl on a steel beam protruding from the south leg of the tower. The sensors are swapped out yearly for calibration and cleaned regularly. The data have been quality controlled through a series of range tests following the standards of NDBC (2009) and manually reviewed to omit periods of faulty data. On 8/4/2022, a Seabird 37 CTD owned by MVCO was installed on a leg of the ASIT tower approx. 2m agl. From 8/4-3/26/2022 this was MVCO's core CTD and the primary source of CTD data for the tower. On 5/25/2023 the upper CTD was replaced and became the primary CTD once again. Sensors are owned and operated by Heidi Sosik and MVCO. 
 

References
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Liu, W. T., Katsaros, K. B., & Businger, J. A. (1979, September 1). Bulk parameterization of air-sea exchanges of heat and water vapor including the molecular constraints at the interface. AMETSOC. Retrieved October 6, 2021, from https://doi.org/10.1175/1520-0469(1979)036<1722:BPOASE>2.0.CO;2. 

National Data Buoy Center, Handbook of Automated Data Quality Control Checks and Procedures (2009). 

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CREATION_DATE       = ’05-October-2021’
UPDATE_DATE         = ’21-June-2022’
UPDATE_DATE         = '24-January-2023'
UPDATE_DATE         = '10-October-2024'
UPDATE_DATE         = '24-February-2025'
creator_name        = 'E. Cinquino'
creator_email       = 'ecinquino@whoi.edu'