Abstract:Chile contains some of the driest areas in the world, yet human activities in these areas require large volumes of water, the result is regions experiencing high water scarcity leading to environmental degradation, conflicts and reduced industrial productivity. The aim of this paper was to quantify the water scarcity in the central and northern regions by calculating the water scarcity index-the ratio of annual water demand to availability. A focus of the paper was to determine the impact of the main industries in each region and investigate the benefit of implementing water reduction strategies within these industries. The water resources of each investigated region were found to be greatly overexploited and particularly so in the region of Antofagasta. The mining industry was found to be the greatest water consuming sector in this region and further analysis demonstrated that the degree of water scarcity could be greatly reduced by the implementation of water reduction strategies. The agricultural sector dominated water demand in all other regions and it was found that upgrading irrigation efficiency alongside reducing consumption in mining improved the situation in all regions. Nevertheless, given the scale of water scarcity, further investigation is necessary to obtain more recent and accurate data and analyze alternative strategies.

No abstract

No abstract

No abstract

Non-technical summary We summarize some of the past year's most important findings within climate change-related research. New research has improved our understanding of Earth's sensitivity to carbon dioxide, finds that permafrost thaw could release more carbon emissions than expected and that the uptake of carbon in tropical ecosystems is weakening. Adverse impacts on human society include increasing water shortages and impacts on mental health. Options for solutions emerge from rethinking economic models, rights-based litigation, strengthened governance systems and a new social contract. The disruption caused by COVID-19 could be seized as an opportunity for positive change, directing economic stimulus towards sustainable investments. Technical summary A synthesis is made of ten fields within climate science where there have been significant advances since mid-2019, through an expert elicitation process with broad disciplinary scope. Findings include: (1) a better understanding of equilibrium climate sensitivity; (2) abrupt thaw as an accelerator of carbon release from permafrost; (3) changes to global and regional land carbon sinks; (4) impacts of climate change on water crises, including equity perspectives; (5) adverse effects on mental health from climate change; (6) immediate effects on climate of the COVID-19 pandemic and requirements for recovery packages to deliver on the Paris Agreement; (7) suggested long-term changes to governance and a social contract to address climate change, learning from the current pandemic, (8) updated positive cost–benefit ratio and new perspectives on the potential for green growth in the short- and long-term perspective; (9) urban electrification as a strategy to move towards low-carbon energy systems and (10) rights-based litigation as an increasingly important method to address climate change, with recent clarifications on the legal standing and representation of future generations. Social media summary Stronger permafrost thaw, COVID-19 effects and growing mental health impacts among highlights of latest climate science.