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Geology topics

M. A. Davies

Publications and source records attributed to M. A. Davies.

2 recordsLinked to original sources

Expert assessment of future vulnerability of the global peatland carbon sink

The carbon balance of peatlands is predicted to shift from a sink to a source this century. However, peatland ecosystems are still omitted from the main Earth system models that are used for future climate change projections, and they are not considered in integrated assessment models that are used in impact and mitigation studies. By using evidence synthesized from the literature and an expert elicitation, we define and quantify the leading drivers of change that have impacted peatland carbon stocks during the Holocene and predict their effect during this century and in the far future. We also identify uncertainties and knowledge gaps in the scientific community and provide insight towards better integration of peatlands into modelling frameworks. Given the importance of the contribution by peatlands to the global carbon cycle, this study shows that peatland science is a critical research area and that we still have a long way to go to fully understand the peatland–carbon–climate nexus.

Nature Climate Change

Monitoring so2 emission at the Soufriere Hills volcano: Implications for changes in eruptive conditions

Correlation spectrometer measurements of sulfur dioxide (SO 2 ) emission rates during the current eruption of the Soufriere Hills volcano, Montserrat, have contributed towards identifying different phases of volcanic activity. SO 2 emission rate has increased from <200 tonnes per day (td −1 ; <2.3 kgs −1 ) in the early stages of dome growth to >550 td −1 (>6.4 kgs −1 ) after July 1996, with the uncertainty associated with any individual measurement ca. 30%. Significantly enhanced SO 2 emission rates have been identified in association with early phreatic eruptions (800 td −1 (9.3 kgs −1 )) and episodes of vigorous dome collapse and pyroclastic flow generation (900 to 1500 td −1 (10.4 to 17.4 kgs −1 )). SO 2 emission rate has proved a useful proxy measurement for magma production rate. Observed SO 2 emission rates are significantly higher than those inferred from analyses of glass inclusions in phenocrysts, implying the existence of a S-rich magmatic vapour phase.

Geophysical Research Letters