Paleoclimate studies and natural-resource management in the Murray-Darling Basin I: past, present and future climates

Abstract

This paper provides an incisive review of paleoclimate science and its relevance to natural-resource management within the Murray-Darling Basin (MDB). The drought of 1997–2010 focussed scientific, public and media attention on intrinsic climate variability and the confounding effect of human activity, especially in terms of water-resource management. Many policy and research reviews make statements about future planning with little consideration of climate change and without useful actionable knowledge. In order to understand future climate changes, modellers need, and demand, better paleoclimate data to constrain their model projections. Here, we present an insight into a number of existing long-term paleoclimate studies relevant to the MDB. Past records of climate, in response to orbital forcing (glacial–interglacial cycles) are found within, and immediately outside, the MDB. High-resolution temperature records, spanning the last 10⁵ years, exist from floodplains and cave speleothems, as well as evidence from lakes and their associated lunettes. More recently, historical climate records show major changes in relation to El Niño–Southern Oscillation cycles and decadal shifts in rainfall regimes. A considerable body of research currently exists on the past climates of southeastern Australia but, this has not been collated and validated over large spatial scales. It is clear that a number of knowledge gaps still exist, and there is a pressing need for the establishment of new paleoclimatic research within the MDB catchment and within adjacent, sensitive catchments if past climate science is to fulfil its potential to provide policy-relevant information to natural-resource management into the future.

本文深入研究了Murray-Darling盆地（MBD）的古气候学及其与自然资源管理的关系。由于1997-2010期间的干旱，科学、公众及媒体的注意力集中于内在气候多样性和人类活动，特别是水资源管理，带来的破坏性影响。许多对政策和研究的评论都提及未来计划却很少考虑气候变化，也缺乏有用的可行知识。为了解未来气候变化，模式者需要更好的古气候资料来制约他们的模式估测。在此，我们将与MBD有关的一系列现存长期古气候研究内容提呈出来。过去的气候记录，对轨道力的反应（冰期-间冰期周期），发现于MBD之内及其近外区。高分辨率的温度记录，跨过去10万年，存在于洪积平原及洞穴钟乳石中，也出现于湖水及与其相关的风成脊中。最近，历史气候记录显示，主要变化与圣婴 –南半球摆动周期相关，也与降雨区域的十年周期相关。关于澳大利亚东南部过去气候的研究已进行了很多，但是大范围的研究还未整理成册。显然还存在着一些知识断层。如果过去气候科学能够有潜力来为将来自然资源管理提供与政策相关的信息，那就很有必要在MBD区域以及相邻敏感区域进行新的古气候研究。

KEYWORDS:

• southeastern Australia
• Murray-Darling Basin
• paleoclimate
• climate forcing
• glacial cycles
• Holocene
• hydrological records
• rainfall

关键词:

• 澳大利亚东南部
• Murray –Darling盆地
• 古气候
• 气候动力
• 冰川周期
• 全新世
• 水力记录
• 降雨

ACKNOWLEDGEMENTS

This manuscript forms the first part of a review that resulted from a workshop funded by the Murray-Darling Basin Authority (June 2009). The Murray-Darling Basin Authority has not had any involvement in the collation of data, the preparation of, or writing of this manuscript.