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Physical Drivers of Earth's Climate
Published in Moonisa Aslam Dervash, Akhlaq Amin Wani, Climate Change Alleviation for Sustainable Progression, 2022
Abolfazl Jalali Shahrood, Abrar Yousuf
Most natural systems in the oceans and all continents have been influenced by zonal climate change and increase in the temperature values. There is evidence that shows that snow, ice and permafrost alterations lead to change in the natural systems. One of the most important changes is the increase in the number of glacial lakes and being greater in terms of their size. On the other hand, permafrost instability and avalanches in the mountainous regions are the other effects. Moreover, ecosystems in the Arctic and Antarctic regions get altered. In addition to the natural systems, evidence shows that hydrological systems have also been affected with many glacier- and snow-fed rivers experiencing an increased run-off and earlier spring peak discharge; besides, lakes and rivers in many regions have become warmer, affecting the thermal structure and water quality.
Risk, Resilience, and System Dynamics
Published in John C. Ayers, Sustainability, 2017
The Great Lakes district of North America provides a good case study of resilience (Carpenter et al. 2001). These glacial lakes provide a range of ecosystem services that fall into two categories: agricultural production and aquatic ecosystem services, which include pollution dilution, municipal water supplies, and recreation. Over time, intensification of agricultural production has come at the expense of aquatic ecosystem services. Much of the problem can be traced to the geochemical behavior of phosphorous, which is the limiting nutrient for plant growth in the region. Initially, a clear-water oxygen-rich lake, agricultural perturbations decreased the resilience of the lake and eventually pushed it into a new state of a turbid, oxygen-poor lake that could not support fish. Unfortunately, this new undesirable state is resilient, so intensive management is required to return the lake to the desired clear-water state. Because it is the critical control on the lake state, phosphorous concentration can be used to measure the resilience of both lake states (clear and turbid).
Glaciers and Glacial Lake Outburst Flood Risk Modeling For Flood Management
Published in Ajai Singh, Wastewater Reuse and Watershed Management, 2019
Nity Tirkey, P. K. Parhi, A. K. Lohani
Worldwide receding of mountain glaciers is one of the most reliable evidence of the changing global climate. Globally, the impacts of climate change include rising temperatures, shifts in rainfall pattern, melting of glaciers and sea ice, the risk of glacial lake outburst floods (GLOFs), sea level rise and increased intensity and frequency of extreme weather events (Ganguly et al., 2010). The climatic change/variability in recent decades has made considerable impacts on the glacier lifecycle in the Himalayan region. The Himalayas are geologically young and fragile and are vulnerable to even insignificant changes in the climatic system (Lama et al., 2009). Glaciers and glacial lakes play an important role in maintaining ecosystem stability as they act as buffers and regulate runoff water supply to plains during both dry and wet seasons. The glaciers and glacial lakes are generally located in remote and inaccessible areas. The inventories are only possible using time series remote sensing data and geographic information system (GIS) technology. The mountain ecosystems are fragile and highly susceptible to global climate changes. GLOF occurs when a dam containing a glacial lake fails. This is mainly due to the glaciers retreat. As glaciers retreat, glacial lakes are formed behind moraine or ice dams or inside the glaciers. A sudden breach in its walls may lead to a discharge of huge volumes of water and debris. Several of such lakes have been burst in the recent past resulting in a loss of human lives and destruction and damages of infrastructure in the valleys below. Glacier-outburst floods cannot be predicted, and therefore, continuous monitoring and mapping, both spatial and temporal, as opposed to a limited frequency point measurement can reduce the devastating impact of such hazards. Sometimes it is not easy to avoid natural phenomena causing disasters such as GLOFs, but a prior knowledge about their nature and possible extent can develop a capacity of disaster management authorities to respond and recover from emergency and disaster events. Similarly, hazard maps cannot stop a disastrous event from happening, but an effective use of hazard maps can prevent an extreme event from becoming a disaster. Himachal Pradesh is a mountain state in Indian Himalayas covering an area of 55,673 km2. Himachal Pradesh has four major river basins namely Satluj, Beas, Chenab, and Ravi. Satluj basin alone covers 45% of the total geographical area of the state (923,645 km2). The basin is very active and experiences regular floods causing widespread damage in the down valleys.
Spatial interpolation of water quality index based on Ordinary kriging and Universal kriging
Published in Geomatics, Natural Hazards and Risk, 2023
Mohsin Khan, Mohammed M. A. Almazah, Asad EIlahi, Rizwan Niaz, A. Y. Al-Rezami, Baber Zaman
Ageta et al. claim that there are three distinct categories of glacial lakes (Ageta, et al. 2000): (1) Unconnected glacial lakes are lakes that are not directly connected to glaciers but may have a glacier within their basin (2) supraglacial lakes (melting ponds), which form on the glacier’s surface downstream; or (3) proglacial lake, which are moraine-dammed lakes that are in contact with the glacier front. Some of these lakes have substantial water storage capacities and are vulnerable to GLOFs. (Floods from glacial lake outbursts) (Salerno, et al. 2012). The geomorphological, climatic, and hydrological characteristics typical of the latitude and altitude at which their hydrographic basins are located; are strongly linked to the lakes’ large chemical and biological variety (Lami, et al. 1998; Kamenik et al. 2000; Sommaruga and Psenner 2001; Laurion, Lami, and Sommaruga 2002). The ecosystems are extremely delicate and vulnerable (Karlsson, Jonsson, and Jansson 2005; Brown, Hannah, and Milner 2007), where climate change greatly impacts their functioning and structure (Stenseth et al. 2002; Wrona et al. 2006; Battarbee et al. 2005; Baudo, Tartari, and Vuillermoz 2007). The glacial lakes are a good indicator for assessing the effects of climate change at high elevations (Richardson and Reynolds 2000; Benn, Wiseman, and Hands 2001).
Glacial lake changes and outburst flood hazard in Chandra basin, North-Western Indian Himalaya
Published in Geomatics, Natural Hazards and Risk, 2018
The global climatic change influences regional climate which in turns has a major impact on the glaciers. Glacier dynamics are closely related to the evolution and development of glacial lakes. The retreat of glaciers reveals further basins resulting in the formation of new pro-glacial lakes and increase in the size of existing pro-glacial lakes worldwide (Carrivick and Tweed 2013; Hanshaw and Bookhagen 2014; Zhang et al. 2015; Cook et al. 2016; Govindha Raj and Kumar 2016). Climatic variations like increase in temperature, precipitation, and evaporation in the glaciated region affect the mass balance of glaciers and results in enhanced snow and glacier melt runoff leading to expansion of glacial lakes due to increased water supplies to the lake.
The role of hydropower in South Asia’s energy future
Published in International Journal of Water Resources Development, 2021
Ramesh Ananda Vaidya, David James Molden, Arun Bhakta Shrestha, Nisha Wagle, Cecilia Tortajada
These risks have to do with environmental and climate risks, such as glacial lake outburst floods (GLOF), high streamflow variability and sediment load changes. It is recognized here that hydropower faces environmental challenges, especially in the light of climate change. These risks are associated with uncertainty in future climate projections due to their coarseness and assumptions about non-climatic factors, such as population dynamics, technologies, land use, economic changes and political uncertainties (IHA, 2019; NDRI, 2017; Ray et al., 2018; Ray & Brown, 2015).