harvests

Climate change and hunger

July 14, 2025 By EarthWise Leave a Comment

Worldwide, people are producing more food than ever, but most of that production is concentrated into only a handful of places. For example, fully one third of the world’s wheat and barley exports come from Ukraine and Russia. Across the globe, several major crop-growing regions, including some in the United States, are heading towards sharp drops in harvests as a result of climate change.

These forthcoming changes are not only bad news for farmers, but they are also bad news for everyone who eats. According to a new study published in the journal Nature, it is going to become harder and more expensive to feed a more crowded and hungrier world.

Specifically, under a moderate greenhouse gas emissions scenario, six key staple crops will see an 11.2% decline by the end of the century, compared to a world without warming. The largest drops won’t be in the poorer, more marginal farmlands, but rather in places that are major food producers. These are places like the US Midwest that has long benefited by having both good soil and ideal weather for raising crops like corn and soy.

When the weather is not ideal, it can drastically reduce agricultural productivity. Extreme weather in many places has already damaged crops. Flooding has destroyed rice in Tajikistan, cucumbers in Spain, and bananas in Australia. Severe storms in the US this spring caused millions of dollars’ worth of damage to crops.

As the climate changes, rising average temperatures and changing rainfall patterns are likely to diminish yields and extreme weather events like droughts and floods could wipe out harvests more often. As climate change intensifies, agriculture is the most weather-affected sector of the economy.

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How climate change will worsen hunger

Photo, posted may 20, 2011, courtesy of Lance Cheung / USDA via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

A sustainable and climate-friendly food

November 22, 2024 By EarthWise Leave a Comment

Researchers predict that climate change will negatively impact the yield and nutritional quality of most staple food crops, including rice, corn, and soybeans, due to factors like extreme weather events, rising temperatures, and altered precipitation patterns, potentially leading to reduced food security globally.

As a result, many experts contend that alternative food sources – like insect farming and seaweed aquaculture – are part of the solution. Additionally, expanding production of climate resilient food crops will also have an important role to play in global food security.

According to a new international study led by researchers from University of Vienna in Austria, chickpeas – also known as garbanzo beans – are a drought-resistant legume plant with a high protein content that can help combat food insecurity amid climate change.

In the study, which was recently published in the journal Plant Biotechnology, the researchers investigated the natural variations of different chickpea genotypes and their resistance to drought stress and achieved promising results. The research team managed to grow many different chickpea varieties under drought stress in a field experiment outside of Vienna. The results demonstrate that chickpeas are a great alternative legume plant that can complement grain farming systems in urban areas.

The study highlights how the decline of plant genetic diversity poses a major threat to plant productivity and harvests. In fact, while there are approximately 7,000 edible crops, two-thirds of global food production is based on just nine crop species.

According to the research team, highly nutritious and drought-resistant legumes such as chickpeas are a “food of the future.”

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Chickpeas – sustainable and climate-friendly foods of the future

Photo, posted March 21, 2020, courtesy of Ajay Suresh via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The global chocolate supply is threatened

May 16, 2024 By EarthWise Leave a Comment

The world is facing the biggest deficit of cocoa in decades. Most cocoa beans are grown in West Africa, where climate change-induced drought has ravaged crops. Harvests are forecasted to fall short for the third consecutive year.

The harvest shortfall has triggered a steep rise in cocoa prices. In fact, cocoa prices have more than doubled in the first four months of this year, and have more than tripled in the past 12 months.

But drought isn’t the only threat: A rapidly spreading virus is also threatening the future of chocolate.

Approximately half of the world’s chocolate originates from cacao trees in Ghana and the Ivory Coast. The Cacao Swollen Shoot Virus Disease is spread by small insects called mealybugs, which eat the leaves, buds, and flowers of cacao trees. The virus is attacking cacao trees in Ghana, resulting in harvest losses of 15-50%.

Pesticides don’t work well against mealybugs. Farmers can vaccinate trees to inoculate them from the virus. But the vaccines are expensive, and the vaccinated trees produce a smaller harvest of cacao.

According to a new paper recently published in the journal PLOS ONE, an international team of researchers has developed a new strategy to combat these pests: using mathematical data to determine how far apart vaccinated trees need to be planted in order to stop mealybugs from hopping from tree to tree. The researchers developed two models that allow farmers to create a defensive ring of vaccinated trees around unvaccinated trees

The research team hopes its models will help farmers protect their crops and achieve better harvests in the future.

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Cacao sustainability: The case of cacao swollen-shoot virus co-infection

Will rising cocoa prices trigger a chocolate crisis?

Photo, posted April 1, 2019, courtesy of Konrad Lembcke via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Winegrowing regions and climate change

April 29, 2024 By EarthWise Leave a Comment

Grapes grown to make wine are sensitive to climate conditions including temperatures and amount of rainfall. The warming climate is already having visible effects on yields, grape composition, and the quality of wine. This has significant consequences on the geography of wine production and is of major concern for the $350 billion global industry.

Winegrowing regions are mostly at the mid-latitudes where temperatures are warm enough to allow grapes to ripen but not excessively hot. The climates are relatively dry so that fungal diseases are not rampant.

Because of the warming climate, harvesting in most vineyards now begins two or three weeks earlier than it did 40 years ago and this affects the grapes and the resultant wines. Temperature changes affect acidity, wine alcohol, and aromatic signatures.

If global temperature rise crosses the 2-degree level, 90% of all traditional winegrowing areas throughout Spain, Italy, Greece, and southern California may become unable to produce high-quality wines. Conversely, areas of northern France, the states of Washington and Oregon, British Columbia, and Tasmania will see improved conditions for producing quality wines.

As the climate warms, winegrowers face new challenges such as the emergence of new diseases and pests as well as an increasing number of extreme weather events. Wine producers are using more drought-resistant grape varieties and are adopting management methods that better preserve soil water.

The changing climate poses many threats to the quality of wines produced in traditional vineyards. In the future, the wine industry may look very different in terms of where and how the best wines are produced.

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A global map of how climate change is changing winegrowing regions

Photo, posted November 14, 2008, courtesy of Curtis Foreman via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio