501 research outputs found

    Atmospheric implications of studies of Central American volcanic eruption clouds

    Get PDF
    During February 1978 a group of scientists from the National Center for Atmospheric Research, several colleges and universities, the U.S. Geological Survey, and NASA used a specially equipped Beech Queen Air aircraft to make 11 sampling flights in Guatemala through the eruption clouds from the volcanoes Pacaya, Fuego, and Santiguito. Measurements were made of SO42−, SO2, HCl, HF, and 11 cations that were in water-soluble form, on samples collected by a specially designed filter pack. Particle size distributions were obtained with a piezoelectric cascade impactor, and the particles were identified by energy dispersive X ray analysis. Evacuated canisters were flown to obtain samples for gas Chromatographic analysis. Some of the conclusions reached are that since most of the sulfur was found to be in the form of SO2, the H2SO4 droplets resulting from major explosive eruptions must largely result from the reaction of SO2 with OH, at the same time depleting the atmosphere of OH; the volume concentration ratio [SO2]/[HCl] always somewhat exceeded unity; and the amount of fine ash remaining in the stratosphere for long periods of time may depend on the crystallinity of the magma. Correlation spectrometry showed that each volcano was emitting 300–1500 metric tons of SO2 per day

    Dating the Siple Dome (Antarctica) Ice Core By Manual and Computer Interpretation of Annual Layering

    Get PDF
    The Holocene portion of the Siple Dome (Antarctica) ice core was dated by interpreting the electrical, visual and chemical properties of the core. The data were interpreted manually and with a computer algorithm. The algorithm interpretation was adjusted to be consistent with atmospheric methane stratigraphic ties to the GISP2 (Greenland Ice Sheet Project 2) ice core, (BE)-B-10 stratigraphic ties to the dendrochronology C-14 record and the dated volcanic stratigraphy. The algorithm interpretation is more consistent and better quantified than the tedious and subjective manual interpretation

    Time to treat the climate and nature crisis as one indivisible global health emergency

    Get PDF
    Over 200 health journals call on the United Nations, political leaders, and health professionals to recognise that climate change and biodiversity loss are one indivisible crisis and must be tackled together to preserve health and avoid catastrophe. This overall environmental crisis is now so severe as to be a global health emergency.

    Time to treat the climate and nature crisis as one indivisible global health emergency

    Get PDF
    Over 200 health journals call on the United Nations, politi- cal leaders, and health professionals to recognize that climate change and biodiversity loss are one indivisible crisis and must be tackled together to preserve health and avoid catastrophe. This overall environmental crisis is now so severe as to be a global health emergency. The world is currently responding to the climate crisis and the nature crisis as if they were separate challenges. This is a dangerous mistake. The 28th Conference of Parties (COP) on climate change is about to be held in Dubai while the 16th COP on biodiversity is due to be held in Turkey in 2024. Read more in the PDF

    Reducing the risks of nuclear war—The role of health professionals

    Get PDF
    In January, 2023, the Science and Security Board of the Bulletin of the Atomic Scientists moved the hands of the Doomsday Clock forward to 90s before midnight, reflecting the growing risk of nuclear war. In August, 2022, the UN Secretary-General António Guterres warned that the world is now in “a time of nuclear danger not seen since the height of the Cold War.” The danger has been underlined by growing tensions between many nuclear armed states. Read more in the PDF..
    corecore