In the aftermath of storms, earthquakes and other natural disasters, affected countries may face more than disease, looting and infrastructural collapse. According to Politics Professor Philip Nel and doctoral student Marjolein Righarts, they're at greater risk of conflict and even civil war.

Now, with an increase in catastrophic weather events predicted as our climate changes, the pair argue the world needs to sit up and start thinking about how it will address the political upheaval that may ensue.

In a world first, Nel and Righarts have taken a fresh look at international data sets covering all the countries of the world over a 50-year period. Some of this data has documented natural disasters - drought, flood, earthquakes, heat waves, volcanic eruptions, tsunami, fire, plague, landslides and insect infestations. Other material identified the onset of civil violence around the world. What the researchers discovered is a statistically significant correlation between the two. "Of course it's not a foregone conclusion that violence will follow disaster," Nel stresses. But under certain conditions, it appears natural disasters can become a catalyst for man-made turmoil.

Righarts explains that the list of critical factors is "motivation, opportunity and incentive".

"Usually there is an existing grievance, and issues like poverty and inequality do tend to be exacerbated by the disaster. But, as well as that, the disaster cannot have been so catastrophic that it completely incapacitated people's ability to act and seek change. Further, aggrieved groups will usually capitalise on circumstances, such as the government or infrastructure being weakened."

In some cases, the natural disaster may directly promote unrest: following the Nicaragua earthquake of 1972, the misappropriation of aid resources ultimately led to an overthrow of the government. Other instances see disaster intensifying existing conflicts over land and resources: the desertification of Sudan is a tragic case in point.

Elsewhere, the very weltanschauung of society is at stake. Out of the 1755 earthquake and tsunami in Lisbon grew an emphasis on secular governance, "as entire theological belief structures, and people's understandings of God's willingness to harm them, were deeply challenged," says Nel.

Generally, conflict lags behind the disaster by around one to two years, Nel and Righarts find, and most vulnerable are developing countries with mixed regime types (neither strongly democratic, nor strongly autocratic).

Under certain conditions, it appears natural disasters can become a catalyst for man-made turmoil.

On that, Nel and Righarts note the compounding conditions of cause and effect for states trying to achieve stable development. "It is said that Hurricane Mitch set back development in affected Latin American countries by a decade," Righarts comments. "And, without development, countries are more conflictprone. It can become a vicious circle."

Nel and Righarts' research has led to a one-day workshop with New Zealand Government on preparing for the security consequences of natural disasters. The aim is to help New Zealand determine an appropriate international response at a time when events from flooding to desertification seem set to increase. This includes considering issues such as early warning systems for countries at risk, to helping with preventive measures such as building codes, disaster relief and early conflict detection.

"These are global issues and they require global solutions," argues Nel.

"It's a moral argument too," continues Righarts. "If it's the developed world that is mostly responsible for climate change, it's surely up to us to help the countries that bear the brunt of changes."