He stretches his arms as far as they will go and stands on tip-toe. “This is how deep the water was,” Chim Ly explains, with a grimace. Above the floor level of his wooden stilt house are dark damp smudges signifying the 2013 high water mark.

Cambodians have experienced flooding for centuries, and heavy rains are even necessary to maintain the agricultural livelihoods of thousands of families. But the increasingly unpredictable water levels in recent years are a big concern for rural communities like Beng Voang, Ly’s village in Banteay Meanchey province. Any worse, and the homes and prospects of some the most vulnerable people will be destroyed.

According to the UN and NGOs working in Cambodia, in 2013 high levels of rain affected more than 1.7 million people and 100,000 families were displaced. Just two years prior, in 2011 similar levels affected 20 provinces resulting in 168 deaths. Moreover, drought is getting ever more severe too, threatening food security in a country where child malnutrition is already a problem.

The World Bank and ratings agency Standard & Poor’s both say Cambodia is one of the world’s most disaster-vulnerable countries. Academics at the United Nations University Institute for Environment and Human Security, and at America’s prestigious University of Notre Dame, agree.

Climate change is a reality, and in Cambodia the risk of natural disasters is aggravated further by deforestation and environmental degradation. Communities in Cambodia may not know these abstract expressions, but they sure know their consequences. They experience them almost every year. And each year, people wonder: what can we expect this time? How can we be better prepared?

Around the world, inadequate and fragmented disaster risk reduction strategies are exacerbating susceptibility to disaster, and hampering all the work going into “sustainable development”. The royal government of Cambodia,

assisted by civil society organisations and development partners, has been working to increase resilience through community-based disaster risk management and new strategies and laws are on the way. But we must all redouble our efforts, from both the grassroots up and the top levels down.

The international community – including a high-level delegation from Cambodia – is meeting right now in Sendai, Japan, to discuss how natural disasters affect us all at the World Conference on Disaster Risk Reduction.

Inevitably, there will be much discussion on simply picking the right words for the final statement. Can we reduce disaster “risk”? Or just get more “resilient”? Should we “mitigate” climate change? Or just “adapt” to it? What is “sustainable development” anyway?

The reality is that all the above are intimately connected. Sendai is important because it is the first event of many in 2015 that will lead international efforts over the coming years – from the UN debate on sustainable development goals to the all-important Paris Climate Change Conference.

In Cambodia, the Joint Action Group of civil society organisations and development partners works to strengthen the resilience of the most vulnerable people. And we feel Sendai must not become just another post-2015 conference. Instead, global leaders should seize the initiative to integrate climate change, disaster risk reduction and sustainable development.

We encourage the delegation of Cambodia to voice the needs of the most vulnerable people; to express the need for global, national and local efforts; and set an example in integrating approaches to the global issues under scrutiny 2015: natural disasters, climate change and sustainable development.

All international leaders ought to commit to information sharing and mutual technical support, while increasing the role of local communities in planning and implementing disaster risk management strategies. We also need to see meaningful inclusion of civil society in planning, implementation and monitoring of disaster management, with indicators to measure it all by.

Sendai is upon us, and ought to be the first step in creating the change we need for the world we want. Once disaster risk is concretely linked with climate change and with the proposed sustainable development goals, it’ll create momentum for the “post-2015” process. So let’s trust that the delegates grasp the nettle and kickstart the 2015 process with cause for hope.

It’s now or never. Because if Sendai becomes just another talk show, by the next time there’s an opportunity for action, it could be too late for Beng Voang village. And for many, many others like it.

Caroline McCausland is the country director of ActionAid and Piotr Sasin is the country director of People in Need. This editorial was written on behalf of the Joint Action Group, an informal coalition of civil society organisations working on disaster risk reduction in Cambodia.