Currently Dr. Dar is a Fulbright Postdoctoral Fellow with Professor Welker at the University of Alaska Anchorage.  Shaakir is investigating: a) snow pack water vapor and snow isotope (δ17O, δ18O, δ 2H) profiles in winter and during the spring melt season and b) how climate oscillations interact to control the spatial and temporal precipitation isotope properties across the USA.  This continental study is using 20 years of weekly precipitation isotope values from 75 sites across the US in the analysis.  Dr. Welker’s US Network for Isotopes in Precipitation (USNIP) makes this globally unique study possible. 

Dr. Dar’s research in Finland will be a further extension of his research addressing processes associated with the water cycle.  He will be using water isotope forensics to delineate the fingerprint of sublimation as snow transitions from the solid phase of water into the vapor phase.  This geochemical fingerprint is theoretically different from ocean or lake water evaporation from liquid to vapor.  These field studies will be carried out at the Sodankyla and Pallas Research Stations and will be complemented with controlled winter environment studies at the University of Oslo in cooperation with Dr. Lena Tallaksen and her research group.

This research titled “iSUBLIME” (Isotopes in sublimation by laboratory and in-field meterological experiments) is critical today as the Arctic’s water cycle is under amplified change including greater ice and snow melting.  The transport of solid water (snow and ice) into vapor via sublimation is contributing to the atmosphere’s water vapor pool.  This injection of sublimated water vapor into the atmosphere is occurring in conjunction with greater evaporated vapor being injection from an increasing ice free Arctic ocean. Distinguishing the differences in the isotopic fingerprints between sublimation and evaporation water vapor sources and subsequently precipitation sources, will assist in understanding the importance of sublimation compared to evaporation in the Arctic’s water cycle today and in the future. 

These sublimation isotopic forensics studies by Dr. Daar are complemented by Professor Welker’s Arctic Ocean evaporation isotopic fingerprint measurements using the US Coast Guard Healy icebreaker over the past several years.

 

Photo: Dr. Dar, standing in front of the Finnish flag is with Dr. Welker in front of the US flag; a representation of the international collaboration that is at the core of Dr. Dar’s Fulbright and his Marie Curie back-to-back postdoctoral fellowships.