1. ICELAND’S GRIMSVOTN ERUPTS SATURDAY, MAY 21, 2011 Walter Hays, Global Alliance for Disaster Reduction, University of North Carolina, USA

2. ICELAND A LAND OF FIRE (VOLCANOES) AND ICE

3. Iceland lies on the Mid-Atlantic Ridge, the highly volatile divergent boundary between the Eurasian and North American tectonic plates that is marked by earthquakes and volcanic eruptions.

4. ICELAND AND PLATE TECTONICS

5. GRIMSVOTN: ICELAND’S MOST ACTIVE VOLCANO

6. The Eyjafjallajökull Volcano in Southern Iceland

7. GRIMSVOTN Iceland's most active volcano, Grimsvotn, located at the heart of its biggest glacier Vatnajoekull, started to spew smoke and lava late on Saturday.

8. THE ASH PLUME FROM GRIMS- VOTN REACHED 20 KM (12 MI)

9. AIR TRAVEL AFFECTED The ash plume, which was more than twice the height of last year’ eruption of EYJAFJOELL, led to the establishment of “no fly zone” of 220 km (120 mi) in all directions around the summit, leaving planes grounded and closing airspace across Iceland.

10. EYJAFJOELL’S ASH PLUME ONLY REACHED 9 KM (5.6 MI)

11. BUT, EYJAFJOELL’S IMMEDIATE IMPACT ON AIR TRAVEL WAS WORSE In 2010, EYJAFJOELL’s vertical ash plume, which, unlike Grimsvotn’s, was comprised of very fine silica ash, shut down large portions of European airspace for almost a month, and forced 600 people to evacuate from their homes.

12. Eyjafjallajökull: UNDER A GLACIER; MARCH 27, 2010

13. EYJAFJALLAJOEKULL: VOLCANO UNDER A GLACIER

14. HEAVY FLOODING: APRIL 14, 2010

15. HEAVY FLOODING LOCALLY: APRIL 14, 2010

16. HEAVY FLOODING WASHES OUT ROAD: APRIL 14, 2010

17. (DARK) ASH CLOUD OVER ICELAND: APRIL 15, 2010

18. ASH CLOUD FROM APRIL 14 ERIPTION

19. A dark and spectacular volcanic cloud spread over Britain and toward continental Europe on Thursday, April 15, forcing airlines to cancel thousands of flights as it drifted at high altitude south and east from the continuing eruption in Iceland.

20. The ash cloud, made up of minute particles of silicate that can severely damage jet engines, left airplanes stranded on the tarmac at some of the world’s busiest airports.

21. MAP OF AIRPORTS CANCELLING FLIGHTS: APRIL 15, 2010

22. THE ERUPTION CONTINUES: ICELAND; APRIL 17, 2010

23. STEAM AND ASH CLOUD: APRIL 18, 2010

24. “DIRTY THUNDERSTORM” APRIL 17, 2010

25. APRIL 19: Eyjafjallajökull is still erupting.