Page - 23 - in options, Volume winter 2017/2018

americas 23 regional focus www.iiasa.ac.at winter 2017/18 ◼ options One of the most serious threats to our environment is prolonged periods of drought. Droughts can severely impact food security, lead to increases in heat-related illness, cause wildfires, and destroy the natural habitat of plants and animals that preserve the delicate balance in our ecosystem. In recent years, California has been hit especially hard by prolonged drought. Since 2011, the state has seen reduced productivity in agriculture, with crop revenue loss estimated at greater than US$810 million, lack of water availability for irrigation and hydropower, and progressive depletion of groundwater storage. In 2014 alone, the drought was responsible for more than $2.2 billion in statewide losses. In a study published in the journal Geophysical Research Letters, Yoshihide Wada and his team showed that human activities have increased the occurrence and intensity of the hydrological drought in California. According to the study, human activities, such as irrigation, doubled the likelihood of the severe 2014 drought in California. The study also found that regulating water reservoirs upstream could intensify drought intensity downstream when storing water and alleviate drought when releasing more water during cropping periods. “Drought is usually associated with climate extremes, such as dry spells. However, human water management can be equally important for understanding why droughts are getting more severe in recent years,” explains Wada, IIASA Water Program deputy director. “Irrigation and dam operations can have large impacts on changing drought characteristics in California at large.” JS International migration is a phenomenon that constantly alters the social makeup of large cities across the globe. In some cases, immigrants who move to a new city associate primarily with other immigrants, leaving the immigrant population fairly isolated from the rest of the community. Montréal, home to roughly 85% of those who immigrate to Québec, has a history of high levels of immigration and international mobility. As such, it is a good indicator of how immigrants may choose to integrate with their new communities. Historically, this has been difficult to accurately measure, since most similar studies ignore the fact that many immigrants are limited by economic, social, and cultural factors, and isolation is therefore not out of choice. In a study published in the journal Applied Spatial Analysis and Policy, IIASA researcher Guillaume Marois avoided the descriptive indicators that commonly fail to take into account the wide variety of structures in Analyzing the impact of human activities on the California drought Further info Marois G (2017). A statistical approach for analyzing residential isolation and its determinants for immigrant communities: an application to the Montreal metropolitan region. Applied Spatial Analysis and Policy: 1-29. [pure.iiasa.ac.at/14518]. Guillaume Marois marois@iiasa.ac.at immigrant communities, which is what many similar studies use as their primary method of measurement. “I applied statistical modeling that allowed the net propensity to live in isolation to be identified,” explains Marois. “I found that once we take into account the composition of groups, no immigrant communities are particularly segregated in Montréal. However, some vulnerable groups in terms of education, income, or language, are much more isolated than others. In consequence, public policies should take this heterogeneity into account.” These findings could help shape public policy towards these immigrant communities. JS Further info He X, Wada Y, Wanders N, & Sheffield J (2017). Intensification of hydrological drought in California by human water management. Geophysical Research Letters 24 (4): 1777-1785. [pure.iiasa.ac.at/14339] Yoshihide Wada wada@iiasa.ac.at Measuring residential isolation among Montréal’s immigrants