Journal
FARADAY DISCUSSIONS
Volume 200, Issue -, Pages 229-249Publisher
ROYAL SOC CHEMISTRY
DOI: 10.1039/c7fd00006e
Keywords
-
Categories
Funding
- European Commission
- national research program in Germany (BMBF)
- national research program in France (INSU-CNRS)
- national research program in France (MESR)
- national research program in France (CNES)
- national research program in UK (NERC)
- Natural Environment Research Council [ncas10005, NE/H002944/1, ncas10008, NE/G00479X/1, ncas10009] Funding Source: researchfish
- NERC [ncas10005, NE/G00479X/1, ncas10008, NE/H002944/1] Funding Source: UKRI
Ask authors/readers for more resources
IAGOS (In-service Aircraft for a Global Observing System) performs long-term routine in situ observations of atmospheric chemical composition (O-3, CO, NOx, NOy, CO2, CH4), water vapour, aerosols, clouds, and temperature on a global scale by operating compact instruments on board of passenger aircraft. The unique characteristics of the IAGOS data set originate from the global scale sampling on air traffic routes with similar instrumentation such that the observations are truly comparable and well suited for atmospheric research on a statistical basis. Here, we present the analysis of 15 months of simultaneous observations of relative humidity with respect to ice (RHice) and ice crystal number concentration in cirrus (N-ice) from July 2014 to October 2015. The joint data set of 360 hours of RHice-N-ice observations in the global upper troposphere and tropopause region is analysed with respect to the in-cloud distribution of RHice and related cirrus properties. The majority of the observed cirrus is thin with N-ice <0.1 cm(-3). The respective fractions of all cloud observations range from 90% over the mid-latitude North Atlantic Ocean and the Eurasian Continent to 67% over the subtropical and tropical Pacific Ocean. The in-cloud RHice distributions do not depend on the geographical region of sampling. Types of cirrus origin (in situ origin, liquid origin) are inferred for different N-ice regimes and geographical regions. Most importantly, we found that in-cloud RHice shows a strong correlation to N-ice with slightly supersaturated dynamic equilibrium RHice associated with higher N-ice values in stronger updrafts.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available