Disruption of typical weather patterns. Scorching drought interrupted by erratic rainfall. Water shortages and then, suddenly, a deluge of flooding. Poor crop yields; an increase in food prices; dreadful hunger. This is the future Cambodia is facing as climate change takes its toll – and farmers are already feeling the effects, experts have warned.

In Banteay Meanchey province, the floods of last year’s rainy season cost Prak Savay his entire rice paddy. Before the downpours, he had 5.5 hectares of land in which he had invested $500. Afterwards, he was forced to sell what remained for $250.

Before last year, the 34-year-old father-of-two was able to farm in both dry and rainy seasons for ten years. But now, he can only afford to plant rice during the rainy season.

“I am a farmer so I am dependent only on farming, but my land gets worse and worse every year,” he said.

Savay’s situation is far from isolated. Extreme weather patterns pose a threat to food security all over the world, according to the UN’s Intergovernmental Panel on Climate Change (IPCC) report Climate Change 2014: Impacts, Adaptation, and Vulnerability, published last week. The study said that increases in global crop yields needed to sustain a growing population have slowed over the past 40 years. They are likely to keep declining at rates of up to two per cent a decade.

Cambodia, where 90 per cent of the country’s poor live in rural areas, according to the World Bank’s latest figures, will be among the hardest hit.

Chhinh Nyda is a lecturer in environmental studies at the Royal University of Phnom Penh, where he specialises in drought vulnerability in rural Cambodia. He wrote in an email earlier this week that due to climate change, the rainy periods are going to be shorter, and more rainfall will be concentrated during the rainy period.

He added that there will be more rainfall in late July and September, and that August will see a longer, drier period. There will then be less rainfall in late November, he added, saying: “Farmers who depend on rain-fed farming to grow their crops are going to face more disasters, especially floods and drought.”

Rice production is expected to decline, leading to the migration of farmers to seek work in urban areas. Increased pressure will be put on urban infrastructure; diseases such diarrhoea, dengue fever and malaria will be more common with increased flooding; food prices will escalate; malnutrition will be rife.

Socheath Sou, co-ordinator at the Cambodia Climate Change Network (CCCN), a membership organisation for groups and individuals with an interest in the field, said that his members have reported a 30 per cent decline in rice yields over the past 10 years. This has led to a rise in people migrating to the capital to look for work.

“Phnom Penh is really crowded now compared to 10 years ago. And that causes problems for the city: health problems, infrastructure problems, education problems, security, safety,” he said.

Sharon Thangadurai, Oxfam’s associate country director, listed Battambang, Svay Rieng, Prey Vieng, Kampong Thom, Kampong Chhnang and Pursat as particularly vulnerable to erratic rainfall. Small producers and farmers are affected the most, he continued, because they have less land to fall back on. A decrease in food production leads to a rise in food prices. “Food security is a major issue,” he said, speaking from Oxfam’s office near Toul Kork last week.

A lack of food also presents an increased risk of malnutrition. Thangadurai continued: “If you’re not eating quality food, that’s impacting the family’s health. There’s not enough food with nutritional value for the children, then they have to spend money on health services.”

There are a variety of health dangers linked to flooding, such as water-borne diseases like diarrheoa and cholera, and mosquito-borne diseases like malaria and dengue fever. Sou added that respiratory problems have been linked with drought conditions, saying: “When the temperature increases, some people find it very hard to breathe.”

When it comes to cause and effect, Cambodia’s farmers tend to think on a local level. Am Earn, also a farmer in Banteay Meancheay province, said: “My wife and I don’t understand much about climate change, but we think flooding and drought are the result of forest destruction.”

The 48-year-old father of six has three hectares of land where he grows and farms rice, cassava, corn and soybeans. But he said that both flooding and droughts have destroyed his crops, adding: “My family has not had enough food to eat because of the floods and droughts in the past few years.”

Thangadurai said that this line of thinking – linking the rise in extreme weather patterns with deforestation rather than global carbon emissions – is common. It’s something tangible that farmers can get their heads around, he said.

He continued: “If you ask the communities if it’s climate change that’s impacting them, they might not understand, but they know about how weather affects the crop yields, and they link it with the massive deforestation that is happening here.”

This makes sense: whatever the levels of carbon emitted on a global scale, in Cambodia, deforestation exacerbates the situation. According to a study published last autumn in the journal Science, the country has lost seven per cent of its forest coverage over the past 12 years, a rate which is the fifth fastest in the world.

But in Cambodia and other parts of the region, the conversation is already about adaptation. According to Amalie Obusan, regional climate and energy campaign coordinator at Greenpeace Southeast Asia, the situation has already come so far that many people across the world already need to adapt.

“In vulnerable regions like Southeast Asia, there is a need to prioritise adaptation primarily due to existing climate realities,” she said.

CCCN’s work involves sharing knowledge and expertise between member organisations in the form of conferences and workshops, as well as training farmers in adaptation methods. It’s often difficult to change their perceptions, Sou said, because their farming practices have been passed down through generations of ancestors.

But in some provinces, farmers have already started to adapt. Sou pointed to Takeo in particular: “They know how to get water during the dry season: they dig a well in the middle of the rice field. They have been adapting very well.”

Farmers elsewhere are taking note. Theng Theary, 33, grows mangoes and limes in S’ang District, Kandal province. Because of the well on her plot, she said, she and her family are never short of water during dry spells.

“I don’t worry about drought, because I have the well, and I can transfer water from there onto the plants,” she said at her farm earlier this week, as her two young sons played by her feet.

Nyda would recommend harvesting as much rainwater as possible as a crucial adaptation technique. “Building more dikes, check-dams, reservoirs are the best options. At the same time, water management schemes should be widely promoted and well adopted by farmers,” he said.

He added that subsistence farming, whereby produce is intended to provide for the basic needs of the farmer, and rain-fed farming, which relies on rainfall for production, are particularly exposed to climatic hazards.

Oxfam is also trying to shift farmers’ reliance on rain-fed and subsistence farming.

“Seventy-five per cent of farming is all rain-fed,” Thangadurai said. “At the moment, farmers don’t have a safety net to support their livelihoods, because it’s based on subsistence farming – they grow, they finish and if they are impacted with disasters like floods and drought, they don’t have the resistance to come back.”

He added: “Oxfam tries to bring in adaptive methodologies and techniques of farming. A very effective water irrigation system might help a poor family, and shouldn’t be very expensive.”

For Theary, her well has helped her through the current dry season.

“In the past two years I haven’t noticed any change,” she said. “My fruit has been growing just the same.”

Adaptation methods have also helped Am Earn. After he participated in climate change workshops organised by a local NGO over the past year, he has adapted his technique to improve the yield of his rice paddy. He said: “Before, I planted the rice paddy in the rainy season and cassava, corn and soybean in the dry season. Now I grow the corn and soybean crops at the beginning of the rainy season and I grow the rice crop and the cassava in the beginning of the dry season.”

But within the narrative of climate change, most stories are bleak. Obusan insisted that a massive reduction of carbon emissions is needed in order to slow warming and make adaptation easier.

“The opportunity in many countries in Southeast Asia, including in Cambodia, is to hold the rest of the world to account for finding solutions to the impacts of climate change – many of these impacts regularly and disproportionately affect our region, yet we are least responsible,” she said.

She added: “Greenpeace clearly calls on developed countries to drastically reduce carbon emissions.” Additional reporting by Khouth Sophak Chakrya, Vandy Muong and Sok Lak.