OMI SO 2 Product Status and outlook N. Krotkov 1, A. Krueger 2, K. Yang 1, S. Carn 2,P. K. Bhartia 3, K. Evans 2 1. Goddard Earth Sciences and Technology (GEST) Center, UMBC, USA 2. Joint Center for Earth Systems Technology (NASA/UMBC), UMBC, USA 3. Laboratory for Atmospheres, NASA Goddard Space Flight Center, USA

OMI SO 2 data publicly released in 2006 The operational OMI SO 2 product contains retrieved SO 2 amounts for 3 separate SO 2 vertical profiles: Explosive eruption clouds [15 km altitude, large SO 2 loading, >50 DU] – NEW Linear Fit algorithm Passive volcanic degassing [5 km altitude, – NEW Linear Fit algorithm Anthropogenic SO 2 pollution; low altitude volcanoes [<3 km altitude (PBL), low SO 2 loading] - New AMF, background correction

SO 2 Level 2 HDF data access web site:

New volcanic algorithm: better retrievals in large volcanic clouds Kai Yang, N.A.Krotkov, A.J. Krueger, S.A. Carn, P.K. Bhartia, and P.F. Levelt, Retrieval of large volcanic SO2 columns from the Aura Ozone Monitoring Instrument (OMI): comparison and limitations, J. Geophys. Res., AURA special issue, submitted, Apr Provisional algorithm Operational algorithm

New volcanic SO2 web site:

New feature just started

Tracking SO2 plumes, Etna April-May 2007 April 30May 1 st May 2 nd

Construction of SO 2 mass time-series started Daily OMI measurements Calculate SO 2 burdens Threshold (e.g., >0.6 DU = volcanic) Background subtraction Noise statistics in SO 2 -free region Daily SO 2 burdens Baseline emission data Ambrym

A-train: OMI/CALIPSO lidar ‘first light’ - 7 June 2006 [Credit: CALIPSO Team, NASA Langley] Carn, S.A., N.A. Krotkov, K. Yang, R.M. Hoff, A.J. Prata, A.J. Krueger, S.C. Loughlin, and P.F. Levelt (2007). Extended observations of volcanic SO2 and sulfate aerosol in the stratosphere, Atmos. Chem. Phys. Discuss.

A-train: OMI/CALIPSO lidar - Rabaul (PNG) aerosol cloud CALIPSO - Oct 14, 2006 OMI - Oct 14, 2006 Cloud altitude ~16 km Cloud thickness ~1-2 km

GOME-2/OMI/AIRS SO 2 : Nyamuragira (Nov 2006) OMI AIRS

Summary: Volcanic OMI’s high sensitivity and global coverage permits detection and tracking of nearly all significant volcanic eruption clouds, providing opportunities for trajectory model validation. A-Train sensors can be used to measure/infer volcanic cloud altitude. Up to six SO 2 retrievals will soon be available daily in NRT. OMI is an economical and effective tool for monitoring pre-eruptive SO 2 degassing on a regional or local (single volcano) scale.

SO 2 pollution over China >50% of China’s energy is derived from coal burning. SO2 emissions increased at a rate 35%/decade in China’s sulfate aerosol loading has increased by 17%/decade in [Massie, Torres and Smith 2004] 25.5 million tons of SO2 was emitted by Chinese factories in 2005 up 27% from 2000 OMI can observe SO 2 emissions in the planetary boundary layer (PBL) over China on a daily basis and is able to track individual pollution plumes outflow to Pacific. Krotkov, N, A., S. A. Carn, A.J. Krueger, P.K. Bhartia, K. Yang, Band residual difference algorithm for retrieval of SO2 from the AURA Ozone Monitoring Instrument (OMI), IEEE Transactions on Geoscience and Remote Sensing, AURA special issue, 44(5), , 2006

Ecuador/S. Colombia volcanoes PERU La Oroya copper smelter Daily SO 2 emissions (kilotons) Sept Sept 2005 Ilo copper smelter Average SO 2 map from OMI Carn, S.A., N.A. Krotkov, A.J. Krueger, K. Yang, P.F. Levelt, "Sulfur dioxide emissions from Peruvian copper smelters detected by the OMI", GRL, 2007.

Megalopolis PP in Arkadia, Greece Rovinari, Turceni, Craiova PP, Romania Maritza Iztok PP, Bulgaria Etna volcano, Italy Yatagan, Yenikoy, Kernerkoy complex in Mugla, Turkey

Atmospheric impacts of oil production OMI measures SO 2 emissions from oil refineries and oil/gas fields in the Gulf States Cumulative SO 2 emissions October 2005 Unknown Iranian source

2 year OMI SO 2 data ( ) Popocatepetl volcano (degassing)

2 year OMI SO 2 data ( ) OMI: Nyamuragira volcano degassing South African power plants (e.g., near Johannesburg); copper smelting More than 90% of South Africa's electricity is generated by the combustion of coal Coal-fired power plants not required to use scrubbers to remove sulfur from emissions Nyamuragira volcano degassing

Average ( ) SO 2 burdens over USA, and China: 25.5 million tons of SO2 was emitted by Chinese factories in 2005 up 27% from 2000 East-Aire’05 experiment Ohio valley PPs

First validation during EAST-AIRE regional experiment over NE China in April SO 2 observations from instrumented aircraft flights are compared with OMI SO 2 maps. SO2 Aerosol Aircraft spirals

April 5: Heavy pollution ahead of cold front : MODIS RGB imagery courtesy of the MODIS Rapid Response Project

The comparison demonstrates that operational OMI algorithm can distinguish between heavy pollution ( April 5 ahead of cold front ):

MODIS RGB imagery courtesy of the MODIS Rapid Response Project April 7: Shenyang area behind cold front

MODIS RGB imagery courtesy of the MODIS Rapid Response Project MODIS RGB + OMI SO2 + trop winds, 7 April 2005

Summary: pollution SO2 1.First validation demonstrates that OMI can distinguish between background SO2 conditions and heavy pollutions on a daily basis. 2.Operational SO2 data need correction for total ozone, SO2 profile, viewing geometry and aerosol effects. 3.OMI IFOV noise ~1.5DU for ideal conditions (near nadir view, no clouds). The noise is expected to decrease with new calibrations (ECS 3 data). 4.Current algorithm Quality Flags are too conservative: reject real pollution. 5.Quantitative use of OMI SO2 data needs collection 3 data

Future validation over China: 2008 East-AIRE – 2 aircraft campaign East-Aire’05 experiment

The End