Following yesterday's horrendous earthquake in Japan yesterday you can follow the tsunami warnings running across the Pacific at the National Data Buoy Center. The flashing diamonds indicate a tsunami warning. I have never seen this website with more flashing diamonds than static until today. Check individual diamonds around Japan and you can see real spikes of data. Each spike is a simple measurement - a simple measurement of amplitude that can wipe out people's livelihoods in a second - a bland statistic that can be a measure of death toll.
Earthquakes, tsunamis - environmental phenoma with serious impacts on people. I suspect Map Action will be in full swing already.