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Correcting the record of volcanic stratospheric aerosol impact: Nabro and Sarychev Peak Mike Fromm Naval Research Laboratory Remote Sensing Division Co-investigators: Gerald Nedoluha, Pat Kablick, James Campbell (NRL) Elisa Carboni, Don Grainger (University of Oxford) Jasper Lewis (NASA GSFC) Aerocenter Seminar, 19 May 2015 Slide 2 NRL & the UTLS: Upper Troposphere & Lower Stratosphere Slide 3 Nabro volcano, Eritrea 13 June 2011 Image credit: Scott Bachmeier Ethiopia Red Sea Saudi Arabia Yemen Slide 4 Volcanicclouds 200+ strong Lieven Clarisse Simon Carn Mike Fromm The 11 micron brightness temperature of the cloud early on was around -73 C. - Dave Schneider 17 km Slide 5 Why does this matter? Whats new here? Is it correct? Slide 6 The Asian Monsoon is big business! Scienceometer = logos x attendees x airline connections Slide 7 Source: The Huffington Post Adam Bourassa: "We used to think that a volcano had to have enough energy that it would put its aerosol and gas directly into the stratosphere in order for it to have a climate effect, but what we see now is that it can be a low altitude as long as it's say next to the Asian summer monsoon and then we can get a climate effect. "This is the first time that we've ever observed volcanic aerosol reaching the stratosphere via some other pathway." The other pathway? Monsoon thunderstorm convection Whats new here? Slide 8 From the volcano textbook - the classic pathway to the stratosphere Convective Thrust Gas Thrust Volcanic cumulonimbus Slide 9 From the cumulonimbus textbook Slide 10 The new volcano pathway SO 2 and/or sulfates Heres what is new, according to Bourassa et al. (2012) Monsoon thunderstorms - India S. E. Asia - garden variety - daily, all summer long - stagnant anticyclone OLROLR This is quite provocative, considering: * The long and winding road from Nabro * Short lifetime of tropospheric SO 2 & sulfate ( Analysis from Fromm et al. (2013) Science Technical Comment MLS SO 2 100 hPa AND > 380 K 14-19 June 2011 MLS SO 2 on 18 June, 00 UTC. These are far from other 18 June observations. And kind of close to the volcano. Whats up with that?!? Is it from Nabro? (yes) Is it from 13 June eruption? (no) Slide 22 Trajectories launched from MLS SO2 feature. z p 16.5 104 384 17.5 88 405 18.5 74 430 Path passes near Nabro on 16 June! On 13 June it is far from volcano. 16 13 Slide 23 Figure 1, Fromm et al., 2014 Meteosat thermal IR brightness temperature minimum and altitude inferred using nearest radiosonde profiles. Slide 24 Correcting the record of volcanic stratospheric aerosol impact: Nabro and Sarychev Peak Journal of Geophysical Research: Atmospheres 3 SEP 2014 DOI: 10.1002/2014JD021507 http://onlinelibrary.wiley.com/doi/10.1002/2014JD021507/full#jgrd51618-fig-0008 http://onlinelibrary.wiley.com/doi/10.1002/2014JD021507/full#jgrd51618-fig-0008 Tropopause Micropulse lidar, Sde Boker, Israel, the day after Nabro 14 June 2011 Nabro aerosols were in the stratosphere right away, and far from the Monsoon. Slide 25 20 16 12 8 4 0 IASI SO 2 Height (km) 14 June 2011, 0740 UTC http://www.volcano.si.edu/volcano.cfm?vn=221101 From Smithsonians Global Volcanism Bulletin: The initial Toulouse Volcanic Ash Advisory Center estimates cited [herein] were made in the time-limited operational setting that identifies volcanic ash for aviation safety. Those altitude estimates, which included maximum plume heights on 13 June 2011 in the range of 9.1-13.7 km altitude, have since been reassessed using an array of satellite and ground-based instruments and processing strategies. The revised heights in the subsequent papers often determined plume altitudes above the 16-18 km tropopause and into the stratosphere. Absent in our earlier report but well documented in the papers was evidence of a 16 June 2011 eruptive pulse. Slide 26 Back to 17 Julyin addition to the layer feature, notice something else. * many of the profiles terminate far above the tropopause Back to OSIRIS Slide 27 Journal of Geophysical Research: Atmospheres 3 SEP 2014 DOI: 10.1002/2014JD021507 http://onlinelibrary.wiley.com/doi/10.1002/2014JD021507/full#jgrd51618-fig-0011 http://onlinelibrary.wiley.com/doi/10.1002/2014JD021507/full#jgrd51618-fig-0011 SAGE II Profile Zmin Time Seriesfull mission Mt. Pinatubo eruption Slide 28 What is below the OSIRIS High Zmin? We look for coincidences: Eruption + 5 weeks, over Hawaii Tropopause 21 July 2011 Slide 29 Journal of Geophysical Research: Atmospheres 3 SEP 2014 DOI: 10.1002/2014JD021507 http://onlinelibrary.wiley.com/doi/10.1002/2014JD021507/full#jgrd51618-fig-0017 http://onlinelibrary.wiley.com/doi/10.1002/2014JD021507/full#jgrd51618-fig-0017 21 July 2011 Slide 30 Journal of Geophysical Research: Atmospheres 3 SEP 2014 DOI: 10.1002/2014JD021507 http://onlinelibrary.wiley.com/doi/10.1002/2014JD021507/full#jgrd51618-fig-0016 http://onlinelibrary.wiley.com/doi/10.1002/2014JD021507/full#jgrd51618-fig-0016 OSIRIS Hawaii High Zmin NOAA Lidar CALIPSO OSIRIS all-time maximum 21 July 2011 Slide 31 Journal of Geophysical Research: Atmospheres 3 SEP 2014 DOI: 10.1002/2014JD021507 http://onlinelibrary.wiley.com/doi/10.1002/2014JD021507/full#jgrd51618-fig-0013 http://onlinelibrary.wiley.com/doi/10.1002/2014JD021507/full#jgrd51618-fig-0013 OSIRIS Zmin in terms of Potential Temperature 2007 (no volcano) 2011 (Nabro) Tropopause = 380 K Overworld 20-45N 45-60N Slide 32 Journal of Geophysical Research: Atmospheres 3 SEP 2014 DOI: 10.1002/2014JD021507 http://onlinelibrary.wiley.com/doi/10.1002/2014JD021507/full#jgrd51618-fig-0014 http://onlinelibrary.wiley.com/doi/10.1002/2014JD021507/full#jgrd51618-fig-0014 OSIRIS Zmin in terms of Potential Temperature 2007 (no volcano) 2009 (Sarychev Peak) 20-45N 45-60N Slide 33 Journal of Geophysical Research: Atmospheres 3 SEP 2014 DOI: 10.1002/2014JD021507 http://onlinelibrary.wiley.com/doi/10.1002/2014JD021507/full#jgrd51618-fig-0019 http://onlinelibrary.wiley.com/doi/10.1002/2014JD021507/full#jgrd51618-fig-0019 Remedy for the High Zmin: Proxy AOD supplement If (High Zmin) then add.02 to AOD Slide 34 Conclusions: * Point-source, episodic UTLS pathways are notoriously difficult to characterize - between the cracks w.r.t. space-based remote sensing - problem: imputing a geophysical process to an under-sampling issue * Nabros June 2011 eruption involved Classic direct stratospheric injection. * injection altitudes between 16-19 km. * Nabro stratospheric aerosols were in abundance without delay. * No Asian Monsoon role in the stratospheric aerosol injection. * OSIRIS stratospheric aerosol data are biased. * systematic under-sampling of the full stratospheric column * additional biasing in presence of plumes with extinction > 0.0025/km * A High-Zmin AOD proxy strategically brings OSIRIS into greater agreement with other data. * Papers on Kasatochi, Sarychev Peak invoking OSIRIS can be re-assessed. * NASA GISS AOD record has substantial contribution since 2002 from OSIRIS. * Caution called for. Slide 35 from the sulfate aerosol textbook Slide 36 From the abstract Tropospheric SO 2 lifetime is between and 3 days. and the SO 2 textbook. Slide 37 Kasatochi: Kravitz et al. (2010) Slide 38 Correcting the record of volcanic stratospheric aerosol impact: Nabro and Sarychev Peak Journal of Geophysical Research: Atmospheres 3 SEP 2014 DOI: 10.1002/2014JD021507 http://onlinelibrary.wiley.com/doi/10.1002/2014JD021507/full#jgrd51618-fig-0015 http://onlinelibrary.wiley.com/doi/10.1002/2014JD021507/full#jgrd51618-fig-0015 OSIRIS Maximum Extinction Coefficient All-time OSIRIS Maximum Extinction Coefficient: 0.0025/km 750 nm Extinction Coefficient (km -1 ) Slide 39 Sarychev Peak: Kravitz et al. (2011) Aerosol Optical Depth - time series Model OSIRIS Slide 40 Sarychev Peak: ONeill et al. (2012) Slide 41 Slide 42 from Conclusions Sarychev Peak: ONeill et al. (2012) Slide 43 Fig. 2 Altitude profiles of the zonal average aerosol extinction ratio, over all longitudes, for 12- day time periods from June through September 2011, showing the progression of the stratospheric aerosol enhancement from the Nabro eruption on 13 June. A E Bourassa et al. Science 2012;337:78-81 Published by AAAS Slide 44 Correcting the record of volcanic stratospheric aerosol impact: Nabro and Sarychev Peak Journal of Geophysical Research: Atmospheres 3 SEP 2014 DOI: 10.1002/2014JD021507 http://onlinelibrary.wiley.com/doi/10.1002/2014JD021507/full#jgrd51618-fig-0012 http://onlinelibrary.wiley.com/doi/10.1002/2014JD021507/full#jgrd51618-fig-0012 OSIRIS profile Zmin Histogram, full data set thru 2012. Slide 45 Slide 46 from Conclusions: Sarychev Peak: Kravitz et al. (2011) OSIRIS was assumed to be the benchmark (e.g.):