Agricultural Risks to Changing Snowmelt

Snowpacks store cold water in winter, which is later melted in warmer spring months to produce streamflow. Historically, irrigated agriculture has relied on snowmelt runoff as an important seasonal water supply in many regions across the world, such as the western United States.

However, Climate change has already begun to change the spatial and temporal patterns of snowmelt runoff — causing a decreasing magnitude of snowfall and earlier melting of snowpacks. Consequently, irrigated agriculture, which has been depending on snowmelt runoff happening with a certain magnitude, at a specific time, and in a given location, are exposed to potentially important risks under a warming climate.

Although such changes in snowmelt-derived water resources are often cited as a key threat to irrigated agriculture and global food security, previous studies have focused on annual changes in runoff, without resolving the sub-annual changes in water supply and crop-specific water demand.

To characterize such risks, we differentiate surface water supply from three sources: snowmelt runoff, rainfall runoff, and alternative water supply such as inter-basin water transfer. Comparing monthly surface water supply with surface water demand under both the historical climate (1985-2015) and predicted warming scenarios (2°C and 4°C above pre-industrial conditions), we identify where irrigated agriculture has been mostly depending on snowmelt runoff in the past 30 years. Also, we find basins in high-mountain Asia (the Tibetan Plateau), central Asia, central Russia, the western U.S., and the southern Andes are particularly vulnerable to decreasing snowmelt availability in crops’ growing seasons due to a future warming climate.

Therefore, these most risky basins will require increasing additional water supplies by increasing inter-basin transfer, pumping additional groundwater, or consuming water required for other uses. Notably, providing those additional water supplies may sometimes cause additional environmental and social problems, thus improved irrigation practices or crop switching may be needed to ensure food security under changing snowmelt.

Yue Qin

Assistant Professor, Department of Geography

The Ohio State University

Have We Gone Too Far to Come Back?

As geographers and atmospheric scientists, we are keenly aware of the reciprocal and interdependent relationships among human societies and the earth system. Popular understandings of natural disasters such as the recent acceleration of burning in the Amazon [1] and the Australian bush fires arguably overemphasize social drivers, and recent changes, that are political (Brazil) and individual (Australia). What we as a community can contribute is the push to think more systematically, structurally, and historically: how have climate changes over the last 50 years contributed to recent crises? And, given the long-term, dynamically interacting social and environmental systems, what are the prospects for resilience?

Australia, for several months, has been experiencing bush fires on an epic scale. There is a great deal of talk about homes lost, people dead, and smoke clogging the air. However, there are other immediate and long lasting implications to our actions.

The fires have devastated Australia with 30 people dead (including four firefighters), roughly 38,594 square miles of bush, forest and parks across Australia burned [2]. In addition to the landscape change, countless animals have perished and as the smoke clears, we may discover that some of the endangered species inhabiting those regions may very well be extinct.

Our planet, however, has some resiliency. Below are examples of life emerging from the fires as nature attempts to rebound through the flames.

This is heartening, however, bush fires don’t only damage our landscape but they can create dangerous weather patterns to worsen existing fire burning patterns. This can cause unpredictability in the way the fire behaves and endanger those fighting the fire [3].

The fires are still burning and will continue to cause damage. The toll may not be known until long after fires have been extinguished. As Geographers and Atmospheric Scientists, the complexity of how these fires affect our planet, our research, and out understanding of climate change, are both exciting and terrifying. Our planet is resilient, but is it resilient enough to survive human beings? Have we gone too far to come back?


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50 Years of Earth Day: Where are we headed?


This April will mark 50 years of Earth Day. Here at the Ohio State University, we have many events planned this spring to mark the occasion. With this new regular blog feature, OSU’s Department of Geography will take stock, over the course of Spring semester 2020, collectively, of our community’s contributions to understanding significant social and environmental change. Specifically, what do geographers have to contribute to highly visible environmental movements such as Earth Day?

Earth Day is an annual event whose purpose is to advocate for environmental protection. Earth Day is perhaps the most visible symbol of the modern environmental movement, to harness the passion and activism of college students, in making a case to protect air, water and biodiversity resources[1].  Earth Day is celebrated each year on April 22nd, with the ongoing goal to mobilize, advocate and educate for environmental issues. Other issues such as climate change, a green economy, and sustainable agriculture have been incorporated into the goals of the event over time[2].

This semester, our blog will present topical and cutting-edge research on social and environmental change. We will explore some of the front lines of climate change (from South American glaciers to midwestern agriculture), engaging with the politics of environmental data: how scientific knowledge about pollution reflects the efforts and interests of multiple institutions, firms and government bodies, our policies to redesign our economies and cities in anticipation of looming environmental crises, how conservation policy can work against the needs of communities and wildlife in practice, and many other salient issues. Moreover, as geographers, we find common ground in prioritizing social and environmental justice in confronting existential threats wrought by climate change – it is clearer now than ever that societal and environmental challenges are inextricably linked[3]. Faculty, graduate students and visitors to OSU geography will provide weekly posts on their research. Our goal is that we uncover some broader insights as a community. Please check back!


Darla Munroe

Professor and Chair

Department of Geography