at this level until the eruption began. Since that time, emissions of both CO2 and sulfur dioxide (SO2) have been very elevated, sometimes reaching levels in excess of 10,000 tonnes/d. These volcanic gas emission rates are among the largest ever measured in Alaska, though such high values are consistent with an openly degassing volcanic system that is actively extruding lava. Based on measurements and observations from Redoubt's previously observed eruptions, these gas emission rates are likely to drop substantially when the eruption wanes. The combination of gas and ash emission from Redoubt since the beginning of the eruption has on occasion resulted in a brownish-yellow volcanic haze in the Cook Inlet region. The volcanic haze contains small quantities of ash, water vapor, sulfur aerosols, and liquid droplets suspended in the air. The main concerns for human health in volcanic haze consist of ash, sulfur dioxide gas (SO2), and sulfuric acid droplets (H2SO4), which forms when volcanic SO2 oxidizes in the atmosphere. Volcanic haze can be both an eye and respiratory irritant. The State of Alaska Epidemiology Bulletin No. 5 summarizes the health effects associated with volcanic emissions and is available on the web at http://www.epi.hss.state.ak.us/bulletins/docs/b2006_05.pdf. Visual and satellite observations show that by March 27, a deep crater about a half mile (800 m) across formed in the middle of the summit amphitheater, likely from one or more of the explosions during the early stage of the eruption. By April 4, a north/south elongated lava dome, about a half mile (800 m) long had grown out of the new crater, at an elevation of around 8,000 feet (2,400 m) above sea level. Most if not all of this dome was destroyed during the large explosion of April 4. A large amount of ice and snow has been removed from the upper Drift Glacier. The Drift River Valley has also been mostly denuded of snow and is covered with lahar deposits. The latest observations, as of about April 9, show a growing lava dome in about the same place as the previous dome. This new dome is about a quarter mile (400 meters) in diameter, and roughly circular as viewed from above. Prognosis and Ongoing Hazards The 2009 Redoubt eruption began with a series of large explosions on March 22–23, followed by less-energetic dome growth in the summit crater. On April 4, another large explosion occurred, which was in turn followed by