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Capabilities / Atmospheric Observatories / Eastern North Atlantic / Locations

C1

ENA - Graciosa Island, Azores, Portugal

Established

18 February 2012

Latitude

39.0916° N

Longitude

28.0257° W

Altitude

30 meters

Surface Type

Volcanic Soil

Instruments

29 (24 active)

Primary Measurement Types

47 (46 active)

The latest site to join ARM’s set of fixed-location atomspheric observatories began operations in September 2013. Identified as the Eastern North Atlantic (ENA), this facility is located on Graciosa Island in the Azores. The Azores are an island group located in the northeastern Atlantic Ocean, a region characterized by marine stratocumulus clouds. Response of these low clouds to changes in atmospheric greenhouse gases and aerosols is a major source of uncertainty in earth system models.
The islands experience a tepid, oceanic, subtropical climate with mild temperatures ranging anywhere from 59 °F to 80 °F. Light clothes with one or two sweaters/jackets are enough to survive the cooler nights, winter season and occasional rain showers.
Click to enlarge images.

Instruments

Facility View from Sonde Balloon Launcher

Main Entrance

West Hill View

Instruments deployed at ENA - Graciosa Island, Azores, Portugal

aeri

Atmospheric Emitted Radiance Interferometer

2016-07-12 — Currently Deployed

Browse Data

aosmet

Meteorological Measurements associated with the Aerosol Observing System

2014-01-01 — Currently Deployed

Browse Data

aps

Aerodynamic Particle Sizer

2024-01-25 — Currently Deployed

Browse Data

asi

All Sky Imager

2024-05-18 — Currently Deployed

Browse Data

camsite

camera that monitors a site area

2016-10-03 — Currently Deployed

Browse Data

ceilpblht

Boundary-layer height data with CEIL

2013-09-29 — Currently Deployed

Browse Data

co-analyzer

Carbon Monoxide Analyzer

2015-04-24 — Currently Deployed

Browse Data

cpc

Condensation Particle Counter

2013-10-04 — Currently Deployed

Browse Data

csphot

Sunphotometer

2013-09-28 — Currently Deployed

Browse Data

gndrad

Ground Radiometers on Stand for Upwelling Radiation

2013-09-30 — Currently Deployed

Browse Data

irt

Infrared Thermometer

1999-12-31 — Currently Deployed

Browse Data

kasacr

Ka-Band Scanning ARM Cloud Radar

2017-06-14 — Currently Deployed

Browse Data

ldis

Laser Disdrometer

2014-02-27 — Currently Deployed

Browse Data

maws

Automatic Weather Station

2017-05-05 — Currently Deployed

Browse Data

mfr

Multifilter Radiometer

2014-04-14 — Currently Deployed

Browse Data

mpl

Micropulse Lidar

2013-10-02 — Currently Deployed

Browse Data

ozone

Ozone Monitor

2013-10-04 — Currently Deployed

Browse Data

psap

Particle Soot Absorption Photometer

2013-10-04 — Currently Deployed

Browse Data

sebs

Surface Energy Balance System

2014-06-25 — Currently Deployed

Browse Data

sirs

Solar and Infrared Radiation Station for Downwelling and Upwelling Radiation

2024-02-09 — Currently Deployed

Browse Data

skyrad

Sky Radiometers on Stand for Downwelling Radiation

2013-09-28 — Currently Deployed

Browse Data

sonde

Balloon-Borne Sounding System

2013-05-22 — Currently Deployed

Browse Data

wb

Weighing Bucket Precipitation Gauge

2017-07-17 — Currently Deployed

Browse Data

wsacr

W-band Scanning ARM Cloud Radar

2017-06-14 — Currently Deployed

Browse Data

Primary Measurements collected at ENA - Graciosa Island, Azores, Portugal

Aerosol absorption

Aerosol concentration

Aerosol optical depth

Aerosol optical properties

Aerosol particle size

Aerosol particle size distribution

Atmospheric moisture

Atmospheric pressure

Atmospheric temperature

Carbon monoxide (CO) Concentration

Cloud fraction

Cloud location

Horizontal wind

Hydrometeor Size Distribution

Hydrometeor fall velocity

Hydrometeor size

Instrument monitoring non-geophysical variables

Lidar polarization

Liquid water content

Longwave broadband downwelling irradiance

Longwave broadband upwelling irradiance

Longwave narrowband brightness temperature

Longwave spectral brightness temperature

Longwave spectral radiance

Net broadband total irradiance

Nitrogen oxides

Ozone Concentration

Planetary boundary layer height

Precipitable water

Precipitation

Radar Doppler

Radar polarization

Radar reflectivity

Shortwave broadband diffuse downwelling irradiance

Shortwave broadband direct normal irradiance

Shortwave broadband total downwelling irradiance

Shortwave broadband total upwelling irradiance

Shortwave narrowband diffuse upwelling irradiance

Shortwave narrowband radiance

Shortwave spectral radiance

Snow depth

Soil heat flux

Soil moisture

Surface energy balance

Surface skin temperature

Visibility

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Atmospheric Radiation Measurement (ARM) | Reviewed March 2025