By Ignacio A. Jara The Southern Annular (SAM) mode is one of the most important atmospheric phenomenon affecting temperature and precipitation in the non-tropical Southern Hemisphere. Perhaps the clearest sign of its growing importance for the scientific community was the mention of SAM in several talks in the SHAPE session in the AQUA biennial conference…
Continue ReadingBy Ignacio Jara Since the 1980’s a huge amount of time and effort has been put to build a climate-sensitive tree-ring chronology for New Zealand. A noteworthy achievement of this scientific effort was the publication in 2006 of two independent tree-ring chronologies, a 2,300-year record from Silver Pine (Lagarostrobos colensoi) and a 3,700-year chronology from…
Continue ReadingBy Ignacio Jara and Helen Bostock The debate about the role the Southern Alps (New Zealand) uplifting to offset global climate change has experienced a recent renewal with the publication of a couple of new articles. According to the Uplifting Theory, over geological time the tectonic erection of large mountain systems has been associated with…
Continue ReadingBy Ignacio A. Jara It has been widely documented that volcanic aerosols can alter the radiative balance of the atmosphere, producing measurable temperature depressions following large explosive eruptions. Perhaps the most renowned of these cases is the eruption of the mount Tambora in Indonesia, which in 1815 caused a decline of 0.5°C in the Northern…
Continue ReadingWe are pleased to announce that the third workshop of the PAGES Australasia2k Working Group will be held in Melbourne on 26-27 June 2014. This will be a joint meeting with the Australian Climate Change Science Program (ACCSP) project “Variability of Australian climate over the last 1000 years in coupled model simulations and proxy data”….
Continue ReadingA small workshop was held on the 28-29th January 2014 in Auckland to discuss the Southern Hemisphere Westerly Winds and how they might have changed over time. See the SHAPE webpage and scroll down to find a link to the summary pdf. from this recent workshop. Please get in touch with anyone listed if you…
Continue ReadingBy Ignacio A. Jara and Helen Bostock Terrestrial dust is important to the climate system not only because it may alter the solar radiative balance of the earth, but also because it supplies the oceans with key iron (Fe), a limiting micronutrient for phytoplankton productivity in the Southern Ocean. The “Iron Hypothesis” was first proposed…
Continue ReadingBy Helen Bostock Over the last decade the main theory to explain the changes in the atmospheric concentration of CO2 between glacials and interglacials, has primarily focussed on changes in the circulation of the Southern Ocean controlling the release of CO2 from the deep-ocean reservoir. However, there is still considerable debate about the path and…
Continue ReadingMemberships are well and truly due and you can pay these easily online. It is easy, so please get yourself signed up and encourage your colleagues, students and friends. This is a great time to sign new people up, as anyone that joins AQUA now will automatically have their membership extended right through to 28 February 2015. Members…
Continue ReadingWritten by Ignacio Jara, Victoria University Wellington. While the abrupt climate transitions of the glacial termination and the establishment of the present-day modes of climate variation during the Holocene seems to be well characterized in proxy records around the Southern Hemisphere, there is still sparse evidence about the impact of those changes on the migration,…
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