Eureka, Canada

K. Strong (U. Toronto) — Bruker 125HR (operated at 257 cm OPD, 0.004 cm-1 resolution in the mid-infrared), installed in July 2006. Direct-sun solar absorption spectra are collected in a semi-automated operation on clear-sky days from polar sunrise (approx. February 20) until polar sunset (approx. October 20). Three intercomparison campaigns with the Eureka Bomem DA8 FTIR were conducted prior to its removal in 2009: February to April 2007, July 2007, and February to April 2008. Alternating mid-infrared NDACC and near-infrared TCCON measurements have been made on a semi-daily basis since 2010. Operations in 2012 and 2013 were reduced due to funding. Operations since April 2020 have been severely affected by the lack of on-site support due to the COVID-19 pandemic, funding, and restricted access to the Ridge Lab, with NDACC MIR measurements currently limited to campaigns.

P. Woods, B. Bell, C. Paton-Walsh, and T. Gardiner (NPL) – Bruker 120M (0.004 cm-1 resolution) used for intercomparisons and campaigns (see subsequent entries). Measurements in Eureka were made in May 1999 but the data are not in the NDACC archive.

H. Fast (ECCC) and K. Shibata and Y. Makino (MRI) — Bomem DA8 system (0.004 cm-1 resolution) deployed in February 1993 and removed in February 2009. Intercompared with NPL mobile instrument in spring 1999. Data archived for the winters of 1996–2000 and 2003–2006.

T. Nagai (MRI) and O. Uchino (MRI) – Nd:YAG Lidar (1064 and 532 nm; dual polarization) deployed in February 1993. Operations were winter only. Operations were expanded to allow for tropospheric retrievals. Operations suspended after spring 2002. Data exist in the database for the two winters spanning 1993–1995.

K. Strong (U. Toronto) — Stratospheric Ozone Lidar system (SOLID) deployed in February 1993 under PI A. Carswell. Nighttime operations only. SOLID has five detection channels, including one Rayleigh channel (353 nm), and one Raman channel (385 nm, installed in 1994) used for aerosol retrieval. Operation suspended for 2002 and 2003. Operations resumed in 2004–2009 on a campaign basis schedule (~2 weeks in February–March) under PI K. Strawbridge. Operation suspended for 2010–2016 due to technical and funding issues. Operations resumed under PI J. Drummond since 2017 on the ~4–6 week period leading up to polar sunrise in January–March and ~2 week period in October–November. Operations since April 2020 have been affected by the lack of on-site support due to the COVID-19 pandemic, funding, and restricted access to the Ridge Lab. Since 2020 the PI of SOLID and PEARL is Kimberly Strong (University of Toronto).

Early data exist in the database for 1994–1998 in NASA Ames format.

K. Strong (U. Toronto) — Stratospheric Ozone Lidar system (SOLID) deployed in February 1993 under PI A. Carswell. Nighttime operations only. SOLID has five detection channels: two Rayleigh channels for stratospheric ozone and temperature (308 and 353 nm), two Raman channels to improve the ozone and temperature profiles in the presence of aerosols (332 and 385 nm, installed in 1994), and one Raman channel for water vapour (405 nm, installed in 1998). Operation suspended for 2002 and 2003. Operations resumed in 2004–2009 on a campaign basis schedule (~2 weeks in February-March) under PI K. Strawbridge. Operation suspended for 2010-2016 due to technical and funding issues. Operations resumed under PI J. Drummond since 2017 on the ~4–6 week period leading up to polar sunrise in January—March and ~2 week period in October-November. Operations since April 2020 have been affected by the lack of on-site support due to the COVID-19 pandemic, funding, and restricted access to the Ridge Lab. Since 2020 the PI of SOLID and PEARL is Kimberly Strong (University of Toronto).

Early data exist in the database for 1993–1998 and 2004–2009 in NASA Ames format. Since 2017 the data are submitted in HDF format.

K. Strong (U. Toronto) — Stratospheric Ozone Lidar system (SOLID) deployed in February 1993 under PI A. Carswell. Nighttime operations only. SOLID has five detection channels, including two channels used for temperature retrieval: one Rayleigh channel for temperature above 25 km (353 nm), and one Raman channel to improve the temperature profiles in the presence of aerosols (385 nm, installed in 1994). Operation suspended for 2002 and 2003. Operations resumed in 2004–2009 on a campaign basis schedule (~2 weeks in February–March) under PI K. Strawbridge. Operation suspended for 2010-2016 due to technical and funding issues. Operations resumed under PI J. Drummond since 2017 on the ~4–6 week period leading up to polar sunrise in January-March and ~2 week period in October-November. Operations since April 2020 have been affected by the lack of on-site support due to the COVID-19 pandemic, funding, and restricted access to the Ridge Lab. Since 2020 the PI of SOLID and PEARL is Kimberly Strong (University of Toronto).

Early data exist in the database for 1993–1998 and 2004–2009 in NASA Ames format.

D. Tarasick (ECCC) — ECC sondes launched once per week year-round beginning in November 1992, with two additional soundings per week in winter. NDACC data archiving began in 1996 under PI, Fast. Launches are currently taking place at the nearby Eureka weather station (79.99°N, 85.90°W, 10 masl).

K. Strong (U. Toronto) — Two DOAS systems (Horiba/Jobin-Yvon/ISA Triax-180 triple grating spectrometers with thermoelectrically cooled CCD detectors).  The UT-GBS is the primary NDACC instrument ("utoronto001") and is focused on zenith-sky measurements in the visible range.  It was first deployed at Eureka in 1999 for spring campaigns and permanently in 2010.  The PEARL-GBS is the secondary instrument ("utoronto002") and was installed in 2006.  From 2006 to 2010, it made zenith-sky measurements in the visible range, and since 2011, is focused on MAX-DOAS measurements in the UV.