By David MacLennan Cargill chairman and chief executive officer & Carter Roberts President and CEO, World Wildlife Fund From Huffington Post

Extreme weather events scuttling harvests. Skyrocketing food prices causing famine for millions and driving multitudes into poverty. Governments toppling – again – in Pakistan and Ukraine. Massive floods driving millions of refugees from their homes in Bangladesh and putting pressure on neighboring India. Droughts devastating harvests in traditional bread baskets like the U.S. and Brazil. The E.U., in a panicked move, suspending its environmental rules for agriculture and instituting a tax on meat. The world’s top greenhouse gas emitters ultimately banding together to raise a global carbon tax.

The events described above are not the real world, but they could be. They were part of what transpired at Food Chain Reaction a few weeks ago, a high-level crisis simulation in Washington, DC that brought together 65 international leaders to explore how climate change may strain the world’s food system from 2020 to 2030.

What the simulation taught us, is that policymakers attending this week’s U.N. climate summit in Paris cannot afford to neglect food security. The world’s population is on a path to 9.5 billion by mid-century. That means we will have to grow up to 70 percent more food. To make matters more complicated, we’ll have to do so in a changing climate that alters the very way we grow our crops. We must figure out how we can make that happen within the limits of the Earth’s natural resources. We’ve talked long enough. It is time to decide on a course of action that will actually improve the situation.

Will climate change by itself break the global food system in the next 10 to 15 years? That’s unlikely. Prices right now are low and relatively stable. The system has enough resilience to absorb shocks. But add population growth, failed states, armed conflict and political instability to the mix and the picture starts looking a lot more combustible. Places that are already grappling with other strains may well be driven over the edge by climate-induced food price spikes.

That is not some far-fetched scenario. The Arab Spring of 2011 came on the heels of record food prices caused in large part by extreme weather events as far afield as Russia, Ukraine, the U.S., Canada, Australia and Argentina. The protesters who poured into the streets of Arab capitals not only demanded political reform, but also the proverbial ‘bread’.

The current violence in Syria was preceded by a severe drought and widespread crop failures in that country, exacerbated by failed agricultural policies. Hundreds of thousands of impoverished farmers fled to the cities. Mass protests led to civil war and the chaos we see today, most notably with a continued refugee crisis and the savagery of ISIS, that has now reached the streets of Paris and was felt in San Bernardino, California.

To be sure, food and climate were far from the only causes here. But many smart observers have pointed out that they had an impact and added to an already volatile mix. It would be unwise to ignore these analyses.

Food security – ensuring enough safe, affordable and nutritious food for all – is often under-appreciated in climate discussions. It shouldn’t be. What we’ve already seen in recent years should serve as a warning. Increased volatility is the new normal. It’s not a matter of whether some hotspots will erupt, but when. It’s up to all of us to be ready to respond. Having enough food for regions vulnerable to climate-induced calamities is job number one.

As the Food Chain Reaction exercise showed, there are constructive ways forward. The players, an international cast of former cabinet secretaries, parliamentarians, high-level officials from national governments and international institutions, academics, business executives and think tank types, came up with a host of cooperative solutions. Among them: building cross-border information hubs and early warning systems, multilateral water management schemes, initiatives to curb food waste, technology exchanges and – most eye-catching – a global carbon tax.

All of these ideas merit discussion. Some may work, some may not. But what’s most important is that the simulation highlighted the prospects for cooperation. Faced with mounting environmental challenges and international tensions, the players chose long-term thinking and multilateralism over closed borders and the short-term national advantage.

Secluded inside a Washington conference center, far from the searing eye of the media and armed with high-minded intentions, that is, of course, a lot easier than in the real world, where the game is often perceived as zero-sum and national electorates stand ready to punish leniency. But it also shows what can be achieved if actors come together, determined to solve big problems.

That’s why organizations like Cargill, a multinational agricultural business, and WWF, a global conservation organization, are joining hands to delve into these defining issues. In different times we would have been seen as strange bedfellows, but the stakes are high and the clock is ticking. The longer we go without action, the deeper the problem will get and the more disruptive the measures we’ll ultimately need to take. We can meet the challenges ahead, but we must get started now, so we can avoid frantic steps at the eleventh hour.

This post is part of a “Climate Justice” series produced by The Huffington Post, in conjunction with the U.N.’s 21st Conference of the Parties (COP21) in Paris (Nov. 30-Dec. 11), aka the climate-change conference. The series will put a spotlight on populations who are adversely affected by climate change. To view the entire series, visit here at: http://www.huffingtonpost.com/news/paris-cop21/

For more on this story and video go to: http://www.huffingtonpost.com/david-maclennan/will-climate-change-break_b_8727318.html