On recent (2008–2012) stratospheric aerosols observed by lidar over Japan

Abstract

Abstract. An increase in stratospheric aerosols caused by the volcanic eruption of Mt. Nabro (13.37° N, 41.70° E) on 12 June 2011 was first detected by lidar at Tsukuba (36.05° N, 140.13° E) and Saga (33.24° N, 130.29° E) in Japan. The maximum backscattering ratios at a wavelength of 532 nm were 2.0 at 17.0 km on 10 July 2011 at Tsukuba and 3.6 at 18.2 km on 23 June 2011 at Saga. The maximum integrated backscattering coefficients (IBCs) above the first tropopause height were 4.18 × 10−4 sr−1 on 11 February 2012 at Tsukuba and 4.19 × 10−4 sr−1 on 23 June 2011 at Saga, respectively. A time series of lidar observational results at Tsukuba have also been reported from January 2008 through May 2012. Increases in stratospheric aerosols were observed after the volcanic eruptions of Mt. Kasatochi (52.18° N, 175.51° E) in August 2008 and Mt. Sarychev Peak (48.09° N, 153.20° E) in June 2009. The yearly averaged IBCs at Tsukuba were 2.60 × 10−4 sr−1, 2.52 × 10−4 sr−1, 2.45 × 10−4 sr−1, and 2.20 × 10−4 sr−1 for 2008, 2009, 2010, and 2011, respectively. These values were about twice the IBC background level (1.21 × 10−4 sr−1) from 1997 to 2001 at Tsukuba. We briefly discuss the influence of the increased aerosols on climate and the implications for analysis of satellite data.

Global volcanic aerosol properties derived from emissions, 1990–2014, using CESM1(WACCM)

“…(b) Lidar measurements above the tropopause at Geesthacht (grey circles with 1 σ error bars, 53.4°N, 10.4°E) from August 1991 to December 1992 [ Ansmann et al , ], and above 12 km at Tomsk (green curves, 56.5°N, 85.0°E) from January 2006 to December 2013 [ Bazhenov et al , ], are compared to WACCM at 55.9°N, CCMI at 57.5°N, and Sato et al and Vernier et al at 45‐60°N. (c) Lidar measurements above the tropopause at Tsukuba (green curves, 36.1°N, 140.1°E) from January 2008 to July 2013 [ Uchino et al , ] are compared to WACCM at 36.9°N, CCMI at 37.5°N, and Sato et al and Vernier et al at 30–45°N. (d) Lidar measurements above the tropopause at Mauna Loa (green curves, 19.5°N, 155.6°W) from April 1994 to December 2013 [ Hofmann et al , ] are compared to WACCM at 19.9°N, CCMI at 17.5°N, and Sato et al and Vernier et al at 0–30°N.…”

Long-term variation of stratospheric aerosols observed with lidars over Tsukuba, Japan, from 1982 and Lauder, New Zealand, from 1992 to 2015

“…These values indicate that the ratios of the aerosol backscatter to molecular backscatter are 370 and 240 times larger than the average of R − 1 = 0.05 during the period 1997–2004 when the influence of the volcanic eruptions was minimal. Figure a also shows small increases in R between the tropopause and 25 km in 2005, 2006, 2008, 2009, and 2011 after the eruptions of Manam (4°S, 145°E), Soufrière Hills (16°N, 62°W), Rabaul (4°S, 152°E), Okmok (53°N, 168°W), Kasatochi (52°N, 175°W), Sarychev (48°N, 153°E), and Nabro (13°N, 42°E) [ Uchino et al ., ].…”

“…[], Uchino et al . [], and Andersson et al . [] have mentioned, these increases are attributable to a series of volcanic eruptions after 2000.…”

Total volcanic stratospheric aerosol optical depths and implications for global climate change

“…In this study we make use of SAOD retrievals from multiple observing systems: four lidars measuring backscatter at 532 nm, a balloon‐borne particle counter (aerosol sonde), Sun photometers in the Aerosol Robotic Network (AERONET), and two satellite data sets. The polarization lidar at Tsukuba (36.1°N, 140.1°E) provides backscatter integrals both above the tropopause and above 15 km [ Uchino et al ., ]. The lidar based at Tomsk (56.5°N, 85.0°E) makes similar measurements of integrated backscatter both above 12 km and 15 km [ Bazhenov et al ., ].…”