Publications

Amplified mid-latitude planetary waves favour particular regional weather extremes

Publication ID: pub.1001500185

Publication date: 22/06/2014

Keywords: Amplification; Environmental and Socio-economic Impacts; Global; Mid-latitude Weather Extremes; Northern Hemisphere; Northern Polar Regions; Planetary Wave Amplitude Changes; Warming

An increase in extreme weather events in the Northern Hemisphere mid-latitudes has been proposed as a result of amplification of atmospheric planetary waves in the region. This study finds months of extreme weather are associated with amplified planetary waves, with different types of extreme events associated to differing degrees.

Arctic amplification decreases temperature variance in northern mid- to high-latitudes

Publication ID: pub.1011607857

Publication date: 15/06/2014

Keywords: Arctic; Arctic Amplification; Atmospheric Circulation; Climate Change; Climate Variability; Mid- to High-latitude Northern Hemisphere; Model; Polar Jet Stream; Temperature Variance; Weather Extremes

Arctic amplification is thought to be altering the polar jet stream and increasing Northern Hemisphere mid-latitude temperature variability. This study investigates cold extremes in the mid-latitudes and shows that subseasonal cold-season variability has significantly decreased in recent decades. The reduction in variability is partly due to more rapid warming of northerly winds and associated cold […]

Proterozoic oxygen rise linked to shifting balance between seafloor and terrestrial weathering

Publication ID: pub.1042270682

Publication date: 09/06/2014

Keywords: Carbon Cycle; Biogeochemistry; Precambrian

A shift toward higher atmospheric oxygen concentration during the late Proterozoic has been inferred from multiple indirect proxies and is seen by many as a prerequisite for the emergence of complex animal life. However, the mechanisms controlling the level of oxygen throughout the Proterozoic and its eventual rise remain uncertain. Here we use a simple […]

Contribution of semi-arid ecosystems to interannual variability of the global carbon cycle

Publication ID: pub.1032639875

Publication date: 21/05/2014

Keywords: Atmosphere; Australia; Carbon Dioxide; Carbon Sequestration; Desert Climate; Ecosystem; El Nino-Southern Oscillation; Fires; Global; Models, Theoretical; Rain; Seasons; Uncertainty

The unusually large land carbon sink reported in 2011 can mostly be attributed to semi-arid vegetation growth in the Southern Hemisphere following increased rainfall and long-term greening trends.

A mimetic, semi-implicit, forward-in-time, finite volume shallow water model: comparison of hexagonal–icosahedral and cubed-sphere grids

Publication ID: pub.1019942226

Publication date: 20/05/2014

Keywords: Advection; Algorithm; Desirable Properties; Discretization; Grids; Operators; Tests

Abstract. A new algorithm is presented for the solution of the shallow water equations on quasi-uniform spherical grids. It combines a mimetic finite volume spatial discretization with a Crank–Nicolson time discretization of fast waves and an accurate and conservative forward-in-time advection scheme for mass and potential vorticity (PV). The algorithm is implemented and tested on […]

Faster Decomposition Under Increased Atmospheric CO2 Limits Soil Carbon Storage

Publication ID: pub.1044153800

Publication date: 24/04/2014

Keywords: Atmosphere; Carbon Cycle; Carbon Dioxide; Climate Change; Soil

Soils contain the largest pool of terrestrial organic carbon (C) and are a major source of atmospheric carbon dioxide (CO2). Thus, they may play a key role in modulating climate change. Rising atmospheric CO2 is expected to stimulate plant growth and soil C input but may also alter microbial decomposition. The combined effect of these […]