Dynamics of Ice Nucleation along the Central Himalaya, Skardu, Pakistan

Abstract

Freshwater resources are precipitation and ice nucleation, which are vulnerable in environmental density with increasing human population and anthropogenic inclined indulgence, leading to the threat of complete disappearance of ice cover. Regarding global prospects, the Himalayas have grave significance regarding ice resources, and Pakistan's dependency upon fresh water from ice covers is more than 70%. Investigation of ice nucleation in the central Himalayas and Skardu regions in Pakistan indicates that abiotic factors like pH and temperature and biotic factors like bacterial presence in sediments or soil, ice meltwater, stream water and plants play a vital role in ice nucleation. Vegetation is the best habitat for bacteria with movement of 50 to 500 culturable cells/m2/sec (Suzuki et al. 1993, Morris et al. 2004 and Goodnow et al. 1990). Application of Vali's formulation c(T)= {ln (No) – ln (No -N(T))}/A for ice nucleation per bacterial cell shows biotic factors are more significant than abiotic factors. Trees like Cedrus deodara (Roxb.ex D. Don) (common name Diar) family name is Pinaceae showed the most significant tendency among the studied variables for ice nucleation, with ln c(T)= -14.84 as compared to Pinus roxburghii Sargent (botanical name) Chir (common name) Pinaceae (family name) ln c(T) = -15.9. Ice nucleation per cell (ln c(T)) in ice meltwater, stream water and sediment were -16, -15 and -15.14, respectively. P.H.PH range was near to neutral value (7) with the highest 8.4 in deposits and the lowest 7-making range of 1.4. The lowest mean monthly temperature in January from 2000 to 2022 is -12.6 oC (2013), while the warmest mean low temperature is -6.2 oC (2022), as per PMD. These temperature ranges are ideal for heterogeneous ice nucleation, as 50% of drops were frozen in the sample taken from the plants at a temperature of -10 °C. In comparison, stream water showed 35% frozen drops in this study. The research methodology following bacterial tests (H2S and Gram tests) and evaluation of abiotic factors like pH, temperature, wind direction indicates more impactful are biotic factors and low temperature for heterogenous ice nucleation.