For three years, North Pagan Volcano has emitted intermittent volcanic plumes. Composed mainly of steam, the plumes also contained other volcanic gases (such as sulfur dioxide) and occasionally small amounts of ash. By mid 2011, Pagan’s activity was nearly continuous, and NASA’s Moderate Resolution Imaging Spectroradiometer (MODIS), carried on both the Terra and Aqua satellites, detected a plume almost every time there was a clear view. (Satellites provide the only reliable observations of Pagan, as the island has been uninhabited since a major eruption forced residents to leave in 1981.) This natural-color image of Pagan Island from May 7, 2012, was collected by the MODIS instrument on the Terra satellite. A volcanic plume blows westward from the summit of North Pagan Volcano. The plume’s blue tint suggests the presence of sulfur dioxide. Several hours after this image was acquired, the Ozone Monitoring Instrument (OMI) on the Aura satellite detected elevated levels of sulfur dioxide just west of the volcano. NASA image by Jeff Schmaltz LANCE/EOSDIS MODIS Rapid Response Team, GSFC. Caption by Robert Simmon. Instrument: Terra - MODIS

File Photo: Civilians flee past a convoy of United Nations peacekeepers after fighting broke out

The head of the U.N. refugee agency says deepening humanitarian crises across the Middle East and North Africa combined with persistent global economic woes have created a “nightmare scenario.”

U.N. High Commissioner for Refugees Antonio Guterres said the formation of a broad crisis area across Africa encompassing Libya, Nigeria, Mauritania and Somalia poses a major threat to global peace and security.

Guterres told The Associated Press on Friday while there is growing need to deal with humanitarian challenges, the international community has limitations on how many resources it is willing to deploy.

Guterres spoke on the sidelines of a conference in the Central Asian nation of Turkmenistan devoted to the issues of refugees in the Islamic world.

- Sapa-AP-IOL