Attribution of Antarctic ozone recovery to the Montreal protocol requires evidence that (1) Antarctic chlorine levels are declining and (2) there is a reduction in ozone depletion in response to a chlorine decline. We use Aura Microwave Limb Sounder measurements of O3, HCl, and N2O to demonstrate that inorganic chlorine (Cly) from 2013 to 2016 was 223 ± 93 parts per trillion lower in the Antarctic lower stratosphere than from 2004 to 2007 and that column ozone depletion declined in response.

Summer monsoon season 2011 was highlighted with unprecedented rainfall in some districts of Punjab in the second week of August 2011 causing significant damage to public and private properties. An attempt has been made in this paper to identify the observational aspects, main synoptic system, Physical process and thermodynamic features leading to such unusual rainfall in Punjab recorded on 13th August, 2011.

Original Source

Precipitation samples were collected across the Himalayas from Kashmir (western Himalaya) to Assam (eastern Himalaya) to understand the variation of the stable isotopic content (δ 18O and δD) in precipitation associated with two dominant weather systems of the region: western disturbances (WDs) and Indian summer monsoon (ISM).

Original Source

In response to global warming, the Brewer–Dobson circulation in the stratosphere is expected to accelerate and the mean transport time of air along this circulation to decrease. This would imply a negative stratospheric age of air trend, i.e. an air parcel would need less time to travel from the tropopause to any point in the stratosphere. Age of air as inferred from tracer observations, however, shows zero to positive trends in the northern mid-latitude stratosphere and zonally asymmetric patterns.