Children staring blankly at a camera they seem barely to realize is there, flies buzzing around their mouths, their little stomachs swollen – it's an image that many of us are familiar with from Ethiopia's famine during the 1980s.

More than 30 years on, Ethiopia is again facing food shortages as a result of a prolonged drought, the worst in 50 years. Although it has not developed into famine, around 18 million people in Ethiopia are now dependent on food aid.

"Eighty percent of the Ethiopian population work in agriculture, but productivity is generally very low," says Johannes Schoeneberger, of the German society for international cooperation (GIZ) in Ethiopia. "They cannot cope with this kind of weather phenomena."

Historically, extreme weather events – such as droughts – have had the biggest impact on food availability and on its price. Right now, more than 330 million people in India are reported to have been impacted a drought that has resulted in poor harvests and reduced access to food.

Making food global

The number of people suffering from hunger globally halved between 1990 to 2015, according to a report on the UN's Millennium Development Goals. However, globally an estimated 795 million people are still undernourished – and more than 90 million of them children are children.

Under the new Sustainable Development Goals, the UN aims to end hunger by 2030, ensuring everyone has access to enough food, all year round. But as the world's population increases – the UN estimates there will be 9.7 billion people on the planet by 2050 – so too does the pressure on food resources.

Under-nutrition and micronutrient deficiencies "impede health and contribute to conflicts and sluggish economic development" according the new book Analyzing Food Volatility and its Implications for Food Security.

But with countries more connected than ever before, it is not only severe weather phenomena and climatic changes that affect access to food; decisions taken in one country can have knock-on effects in others.

"Biofuel policies, trade disruptions, export bans" as well as increasing "speculation on international commodity markets" are all becoming much more important in food security and food pricing, Matthias Kalkuhl, a development expert at the Mercator Research Institute on Global Commons and Climate Change and one of the authors of Analyzing Food Volatility, told DW.

Food to energy

Rising demand for biofuels, particularly in the United States, is having a huge impact on food availability in developing countries. The US is one of the world's largest producers of corn, which it exports across Central and Latin America, as well as other regions that rely on the crop for food.

But policies to increase the amount of corn being used to make ethanol as a biofuel are leaving these importing countries short.

"The policy was set that you had a fixed requirement – a minimum requirement of ethanol that had to be met every year – and this causes inflexibility," said Kalkuhl. "It required a certain amount of biofuel every year, independent of the global situation for food supply."

That means when harvests are poor, the supply of corn for biofuel remains constant but exports fall - and prices rise.

And it is not only policy decisions made in developed countries that are having a big impact, says Douglas Gollin, professor of development economics at Oxford University. Food price spikes in 2008 caused some Asian states to make decisions about their rice exports that had an effect well beyond their borders.

"A number of developing countries decided to limit exports to ensure supply to their own populations, but it had an impact on poor people in the rest of the world," he told DW.

Betting on food

Higher food prices are a much bigger problem in the developing world. People there are forced to spend a higher proportion of their income on what they eat than in developed countries, where a smaller share of the price of food is based on the raw commodity compared to labor and energy costs, says Kalkuhl. It also impacts the quality of food being consumed.

"If income goes down and food prices go up, then also the diversity of the diet reduces and people focus more on cheap staple foods and less vegetables and fruit and meat – which is important for the diet," he said.

Another problem is food market speculation, where investors bet on the price of food commodities, distorting its pricing. Kalkuhl says this has had a particular impact on prices in Africa and Asia. But there are ways to minimize the impact by encouraging responsible investment.

"Banks go out of their agriculture markets in times of crisis," he said, adding that his institute had been trying to develop early warning systems, which could indicate potential problems in the global food market.

"(These would indicate that) now it's wise to exit the market and to not distort prices additionally with speculative activities or other trading activities," he said.

Going it alone

The impact of food price speculation and food-related policies are driving developing countries away from international markets and prompting attempts to increase self-sufficiency. But there are problems, says Kalkuhl. In it is often more expensive to grow food domestically, and practically more difficult.

In Ethiopia, environmental degradation and soil erosion are some of the biggest obstacles to growing food. According to some estimates, more than a quarter of the country's land has become degraded as a result of deforestation and unsustainable farming practices.

Poverty exacerbates the situation. GIZ's Schöneberger says the land's productivity could be increased with the use of improved agricultural practices, as well as fertilizer, insecticides and modern agricultural machinery. However, most farmers are unable cannot afford these. "The average Ethiopian farmer produces 20 percent on one hectare of what is produced in Europe – and just half the production of neighboring countries like Kenya or Morocco."

But he said programs – by GIZ and others – to rehabilitate arable land and give farmers the chance to increase productivity are helping. Along with therecent arrival of long-awaited rains, they are giving people hope.