Reconstructing tropical cyclone frequency using hydrogen isotope ratios of sedimentary n-alkanes in northern Queensland, Australia
van Soelen, E.E.; Wagner-Cremer, F.; Sinninghe Damsté, J.S.; Reichart, G.J. (2013). Reconstructing tropical cyclone frequency using hydrogen isotope ratios of sedimentary n-alkanes in northern Queensland, Australia. Palaeogeogr. Palaeoclimatol. Palaeoecol. 376: 66-72. dx.doi.org/10.1016/j.palaeo.2013.02.019
In: Palaeogeography, Palaeoclimatology, Palaeoecology. Elsevier: Amsterdam; Tokyo; Oxford; New York. ISSN 0031-0182; e-ISSN 1872-616X, meer
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| Author keywords |
Hydrogen isotopes; Tropical cyclones; Long chain n-alkanes; Tropicalclimates; Queensland Australia |
| Auteurs | | Top |
- van Soelen, E.E., meer
- Wagner-Cremer, F.
- Sinninghe Damsté, J.S., meer
- Reichart, G.J., meer
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| Abstract |
A peat record from Quincan Crater (Queensland, Australia), spanning the past 200 years, was used to test if hydrogen isotope ratios of leaf wax long-chain n-alkanes derived of higher plants can be used to reconstruct past tropical cyclone activity. Queensland is frequently impacted by tropical cyclones, with on average 1-2 hits per year. The most abundant n-alkanes in the peat are C-29 and C-31. Possible sources for long chain n-alkanes in the peat core are ferns and grasses, which grow directly on the peat layer, and the tropical forest growing on the crater rim. Hydrogen isotope ratios of C-27, C-29 and C-31 n-alkanes vary between -155 and -185 parts per thousand. (VSMOW), with the largest variability in the upper 30 cm of the record. For the period 1950-2000 AD the variability in delta D of C-29 alkanes resembles a smoothed record of historical tropical cyclone frequency occurring within a 500 km radius from the site. This suggests that the high number of tropical cyclones occurring in this period strongly impacted the delta D signal and on average resulted in more depleted values of precipitation. In the period before 1900 AD, the variability in the hydrogen isotope record is relatively small compared to the period 1950-2000 AD. This might be the result of lower variability of tropical cyclones during this time period. More likely, however, is that it results from the increasing age span per sampled interval resulting in a lower temporal resolution. Average delta D values between 1900 and 2000 AD are around -167 parts per thousand, which is similar to average values found for the period between 1800 and 1900 AD. This suggests that on average tropical cyclone frequency did not change during the past 200 years. This study demonstrates the potential of stable hydrogen isotope ratios of long chain n-alkanes for the reconstruction of past tropical cyclone frequency. |
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