Earthquakes to tsunamis: How do worldwide disasters compare?

By any standard the natural disasters of the past year have been unprecedented in scale and scope. The international aid organization I work for, the International Rescue Committee (IRC), only rarely responds to natural disasters. The majority of our work is with war-affected populations and in domestic refugee resettlement. But in the past 10 months we have responded worldwide to disasters of historic proportions: the tsunami in Aceh, hurricane Katrina in the United States, and now the earthquake in Pakistan.

What do the numbers in the accompanying chart suggest about the nature of disaster? Three critical facts: Better warning systems and improved evacuation plans are imperative to saving lives in predictable disasters such as tsunamis and hurricanes; spending money on preventive or mitigating measures is likely to be much less expensive than rebuilding after a disaster strikes; when aid is insufficient, vulnerable populations are at greatest risk.

In countries that have few resources and where access by rescue operations is limited, the impact of a disaster is often compounded by the outbreak of disease or the inability to provide sufficient aid to the wounded and displaced.

This has been well documented. Studies of large-scale displacement in the Democratic Republic of Congo, Sudan, and northern Iraq following the first Gulf War reveal that more people die from normally treatable diseases than because of violence.

The lesson here is obvious: Without adequate access to resources it is the most vulnerable - especially children and elderly - who are at the greatest risk. This paradigm applies in both man-made and natural disasters. Compare the aftermath of Katrina, the tsunami, and the earthquake in Kobe with what is now happening in Pakistan. While the response to Pakistan's earthquake is ongoing, there is a growing fear - because of insufficient access, logistic capacity, and resources - of a second deadly crisis stemming from untreated injuries, outbreaks of disease, exposure to the coming winter, and malnutrition.

Such a crisis in the aftermath of Katrina along America's Gulf Coast was avoided because of the myriad interventions of state, federal, Red Cross, nongovernmental, and individual responders to provide healthcare and shelter. While not without problems, this infrastructure is a critical component of limiting a disaster's ripple effect.

Similarly, the unprecedented level of financial support to nongovernmental agencies, many of which have experience in dealing with large-scale displacement, and the swift response of militaries with their logistical capacity, staved off an even greater disaster in the far-flung regions affected by last year's tsunami. Another lesson to be drawn: Financial contributions can, and often do, help save lives.

But money alone does not ensure the most effective response. An abundance of resources means an abundance of responders, which presents its own unique coordination challenges. This was true in the tsunami and with hurricane Katrina.

One of the most significant challenges is to generate information that is critical to an effective response and disseminate it across the broadest spectrum of responders. Admittedly, this is a difficult task. Even in the most developed nations, the scale of a crisis can overwhelm the systems that are in place.

The failures in the first five days after Katrina struck demonstrate just how important coordination, logistics, and flexibility are to an effective early response. The lack of an integrated effort to collect and share information meant that gaps, duplication, lost capacity, inappropriate responses, misunderstanding of roles, and significant time spent searching for answers all hampered the response.

Still, it warrants notice that in the early days of a crisis where large-scale displacement or fatalities occur, a significant level of chaos is bound to ensue. Even the best plans take time to coalesce as responders prepare to deploy. Hurricane Katrina displaced more than 1 million people, more than the most hard-hit area of the tsunami, the island of Sumatra and far surpassing the numbers displaced by the 1995 earthquake in Kobe, Japan. The earthquake in Pakistan has displaced a staggering 3 million people. Putting in place appropriate systems and making them known across the widest array of responders prior to the onset of a crisis is critical to minimizing that period of chaos.

Another critical lesson in these numbers is that disasters are always cheaper, in both human and financial terms, to avoid or mitigate than they are to fix. While hurricanes and earthquakes may not be prevented, looking at the untold human suffering and the billions that will be spent for reconstruction, the figures in the accompanying graphic make a strong case for investing in appropriate building codes, sensible planning, environmental mitigation, and adequate early warning and evacuation plans.

• Mark Bartolini was an International Rescue Committee coordinator for humanitarian assistance during the Bosnian war and most recently served as a technical adviser for a post- hurricane response plan developed by the Louisiana governor's office.