The seasonal tree-ring chronologies that recorded discrete moisture signal for warm and cool season have been used to reconstruct the North America Seasonal Precipitation Atlas (NASPA) by the point-by-point regression method, and the results indicated that they can fairly reprod…
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Icehouses, such as the current glacial state and Late Paleozoic Ice Age (LPIA; ~340 to 290 million years ago), make up less than 25% of the past billion years of Earth’s history and are associated with major environmental change. Thus, exploring climate dynamics during the LPIA …
Tree-ring records collected from living mountain hemlock trees in the southern British Columbia Coast Mountains have been used to provide insights into the character of historical climatic fluctuations and the behaviour of individual climate forcing mechanisms. The relatively sh…
Speleothems are carbonate cave deposits that can preserve a geochemical record of local climate as they grow. Oxygen isotope ratios and trace element concentrations in speleothem calcite provide important continental proxies of past climate change. Conventionally, geochemical an…
An issue that has been the subject of much archaeological attention in recent decades is the collapse of urban centers in northern Mesopotamia at the close of the Early Bronze Age. The causes of this regional contraction have been much debated. One obstacle to resolving this iss…
A ∼2500 year record of hydrologic change from southern Iran is inferred from the mineralogy and stable isotopic composition of bulk and biogenic carbonates archived in Lake Hirom (27o 57'N, 53o52'E). This change is related to regional variations in moisture and to the larger Ind…
Earth climate varies on long and short time scales and its patterns have been derived by a variety of geochemical proxies. The most commonly used paleoclimate proxy is the oxygen isotopic composition in carbonates (δ 18 O). δ18 O, however, is not a direct paleo-thermometer, and …
Various applications of palynology have been used to study case studies from four different parts of the world, namely northern Egypt, offshore Gulf of Mexico, eastern Tennessee (USA), and New Orleans, Louisiana (USA). In these case studies, palynomorphs (spores, pollen, dinofla…
A diatom-salinity transfer function is developed for quantitative palaeosalinity reconstruction, from a data-set of 74 modern diatom samples and limnological data from Spanish salt lakes. Relationships between species and environmental data are explored using principal component…
The Indo-Pacific Warm Pool is currently the warmest region of the modern ocean, with annual average sea surface temperatures upwards of 28°C. As such, it is the largest single source of heat and moisture to the atmosphere. Climate modeling efforts and paleoceanographic reconstru…
Three main objectives in this study were: (1) to examine climate variability throughout the Late Cenozoic and test hypotheses regarding the development of C4 ecosystems and the dynamics of the Asian monsoons in NW China; (2) to reconstruct the diets, habitats, and paleoclimates …
As part of the INTAS funded CLIMAN project into Holocene climatic variability and the evolution of human settlement in the Aral Sea basin, fossil diatoms obtained from Chernyshov Bay in the Aral Sea have been examined in order to reconstruct conductivity and lake level change si…
The Inner Sea of the Maldives is an isolated basin in the Indo-Pacific with significant archival potential for climate-driven sedimentation. In this study, high-resolution bulk sediment data of drift deposits from basinal Site U1467B of Expedition 359 of the International Ocean …
In this work we investigate the low-frequency (decadal-centennial) variability of the climate system in Monsoon Asia using a combination of instrumental, paleoclimate proxy, and climate model data. Understanding this critical component of the climate system is essential for accu…
The surface ocean in the western equatorial Pacific contains some of the warmest water on the planet in the western Pacific warm pool (WPWP). Changes in the size and scope of the warm pool have a significant impact on global climate. With the concern of changes in the extent of …
Long-chain n -alkanes are extensively utilized terrestrial plant biomarkers that serve as paleoenvironment and paleoclimate proxy records. However, robust proxy interpretations require robust calibrations, and a major goal of this work is to ground-truth the interpretative frame…
The work presented in this dissertation focuses on the paleoceanography of the Indonesian Seas over the past 25,000 years; a region that plays a critical role in the global atmospheric and oceanic circulation. The modern oceanography of the Indonesian Seas is very complex due to…
This study is aimed to reconstruct the Holocene temperature history in eastern Canada derived from a 6m peat section at Mer Bleue Bog, near Ottawa, Ontario. Geochemical, image and time-series analysis methods such as oxygen isotope analysis of plant cellulose (δ18Ocel), digital …
Over the past one billion years, Earth’s climate has fluctuated between three stable states on million year time-scales: a warm state in which the poles are ice-free, a cold state in which finite ice caps exist at the poles, and a “snowball” state in which ice sheets extended to…