1. Particles responsible for discolouration of the iconic Taj Mahal identified

Bergin, M. H., S. N. Tripathi, J. Jai Devi, T. Gupta, M. Mckenzie, K. S. Rana, M. M. Shafer, A. M. Villalobos and J. J. Schauer (2014): The discoloration of the Taj Mahal due to particulate carbon and dust deposition, Environmental Science and Technology (in press)

The discoloration of the white marble domes of the iconic Taj Mahal in Agra has been a major environmental concern for quite some time. Works in the last decade have established the entire Indo-Gangetic Plain as aerosol hotspot. Air quality data from Agra, an urban site in the central Indo-Gangetic Plain, also suggest poor air quality in the region. However, the source attribution of the discoloration from aerosols depositing on the white marble was not known. This study analyzes ambient particulate matter as well as the particles deposited on the marble domes. Using the chemical composition derived from the collected samples, the authors further estimated the relative contributions of dust, brown carbon and black carbon to the aerosol optical depth at 400 nm. The reflectance spectrum of the clean marble was compared with that of the three aerosol species. In combination, the surface reflectance spectrum is significantly altered by the dust, brown carbon and black carbon with enhanced absorption at shorter wavelength. 59% of the discoloration is estimated to be the contribution of dust, followed by 38% by brown carbon and 3% by black carbon. The results will help formulating appropriate mitigation measures to restore the aesthetics of the iconic Taj Mahal and counter air pollution problems in the region.

2. Global burden of household air pollution

Reference: Smith, K. R., N. Bruce, K. Balakrishnan, H. A-Rohini, J. Blames, Z. Chafe, M. Dherani, H. D. Hosgood, S. Mehta, D. Pope, E. Rehfuess and others in the HAP CRA Risk Expert Group (2014): Millions dead: How do we know and what does it mean? Methods used in the comparative assessment of household air pollution, Annual review of Public Health, 35: 185-206. The household air pollution has been identified as one of the leading causes of mortality in the recently concluded global burden of disease study. In this article, the authors have estimated that in 2010, household air pollution was responsible for 3.9 million premature mortality and ~4.8% of lost healthy life years globally. The article reports an Indian model of household air pollution and personal exposure. A large fraction of the combustion-derived outdoor PM2.5 in South Asia is attributed to household cooking with the contribution increased from 15% in the year 1990 to 30% in the year 2005. The risk of acute lower respiratory infection from child exposure to household air pollution representative of India (285 µg m-3) was calculated in the range 2.0 to 3.8. In India in 2010 all but 24% of ischemic heart disease in men and 42% in women and 33% of acute lower respiratory disease in children could have been eliminated had there

been no exposure to ambient and household air pollution, and passive and active smoking. The study highlights the seriousness of the air quality issue in India in view of high PM2.5 concentration (both ambient and household).

3. CMIP5 models seriously underestimate aerosol load over India

Reference: Sanap, S. D., D. C. Ayantika, G. Pandithurai and K. Niranjan (2014): Assessment of the aerosol distribution over Indian subcontinent in CMIP5 models, Atmospheric Environment, 87: 123-137.

CMIP5 models were used for climate projection in IPCC AR5. Aerosols play a major role in modulating the climate both directly and indirectly; hence misrepresentation of aerosol burden (and absorption property) would lead to large error in climate forcing. The article examines the model fidelity and biases in simulating aerosol distribution over India in 21 CMIP5 models. Majority of the models show large negative bias in AOD over the Indo-Gangetic Basin with a few overestimating AOD. Underestimation of AOD by most of the models is attributed to underestimation of BC and dust (two major aerosol species in India). The study pointed out the deficiencies and calls for improved representation of aerosols in the current state-of-the-art climate models.

4. Agricultural yield loss in India by short-lived climate pollutants

Reference: Burney, J. and V. Ramanathan (2014): Recent climate and air pollution impacts on Indian agriculture, Proceeding of National Academy of Science, 111: 16319-16324.

Recent studies have shown that India has already been negatively affected by climate change in the agricultural sector. This study presents the impacts of short-lived climate pollutants (SLCP) - black carbon and ozone, on wheat and rice yields in India using statistical models. The authors noticed larger impact of SLCP on wheat yield relative to rice, because wheat's growing season coincides with the large build-up of SLCP in India. The relative impacts of SLCP on the yield loss varied across the states, with Uttar Pradesh showing 50% lower yield (than they otherwise would have been without the SLCP trends) of wheat. The four major wheat producing states suffering most are Uttar Pradesh, Rajasthan, Madhya Pradesh and Chhattisgarh, while the two other states - Punjab and Haryana show insignificant impact. For rice, Tamil Nadu and Andhra Pradesh show relatively higher impacts than other major rice producing states. Overall, the yield loss for wheat attributable to SLCP in the year 2010 alone stands out to be over 24 million tons, which translates to ~5 billion USD. The results imply a growing concern about food security in the future and highlight the importance of implementation of appropriate mitigation measures with co-benefits for climate, health and agricultural yield under warming climate.

1. 2015 European Aerosol Conference in Milan (Italy); September 6-11, 2015

The 2015 European Aerosol Conference (EAC 2015) will be held in Milan, Italy during September 6-11, 2015. Abstract submission deadline is February 27, 2015. More detailed information about this workshop can be found out in the conference website
www.eac2015.it/

2. SOLAS Open science Conference 2015

SOLAS open science conference will be held in Kiehl, Germany during September 7-11, 2015. More detailed information about this workshop can be found out in the conference website:
www.confmanager.com/

3. 9th Asian Aerosol Conference 2015

9th Asian Aerosol Conference will be held in Japan during Jun 24 - 27, 2015. More detailed information about the conference in the website:
aac2015.w3.kanazawa-u.ac.jp/

4. 10th Annual International Symposium on Environment 2015

The symposium will be held in Athens, Greece during May 25-28, 2015. More detailed information can be obtained from the symposium webpage:
www.atiner.gr/environment.htm

5. International Conference on Carbonaceous Particles in the Atmosphere

The international conference on carbonaceous particles in the atmosphere will be held in Berkeley, California, USA during August 10-13, 2015. More detailed information can be obtained from the symposium webpage:
iccpa.lbl.gov/