scholarly journals Late-Holocene Climate Variability in Southern New Zealand: A reconstruction of regional climate from an annually laminated sediment sequence from Lake Ohau

2021 ◽  
Author(s):  
◽  
Heidi Anne Roop
Keyword(s):  
New Zealand ◽  
High Resolution ◽  
Little Ice Age ◽  
Ice Age ◽  
Negative Phase ◽  
Thin Sections ◽  
Southwest Pacific ◽  
Laminated Sediment ◽  
Annually Laminated Sediment ◽  
Instrumental Record

<p>This research aims to improve understanding of synoptic climate systems influencing southern New Zealand and document changes in the intensity and frequency of these systems beyond the historical record by analyzing a 1,350-year annually laminated sediment sequence recovered from Lake Ohau, South Island, New Zealand (44.234°S, 169.854°E). Climatological patterns originating in both the tropics (El-Niño-Southern Oscillation (ENSO), Interdecadal Pacific Oscillation (IPO)) and in the Antarctic (Southern Annular Mode (SAM)) influence year-to-year variability in New Zealand’s climate (e.g. temperature and precipitation). However, the range of natural variability of these systems in the southwest Pacific over time is poorly known because the instrumental record is short (~100 years). The high-resolution record from Lake Ohau offers a unique opportunity to investigate changes in regional hydrology and climate, and to also explore connections to large-scale climate patterns over the last millennium.  Hydrodynamic and hydroclimatic processes that influence and control the production, transport, and deposition of sediment within the Lake Ohau catchment are examined and constrained in order to develop a robust climate record. A key aim is to determine the role that meteorology and climate play in controlling sediment flux. The physical properties and facies of a 5.5-meter-long Lake Ohau sediment core are analyzed using thin-sections, high-resolution X-radiographs scans, and particle-size analyses. Time-series analysis is used to establish links between varve facies, hydroclimate variability and regional synoptic climate types over the instrumental record. Utilizing this climate-proxy relationship, inflow conditions are reconstructed over the last 1,350 years and compared with regional temperature reconstructions to generate a Western South Island paleo-atmospheric circulation index. Relationship between this paleocirculation index and other proxy reconstructions show significant variability in the relative forcing of tropical (ENSO) and Southern Hemisphere highlatitude (SAM) synoptic climate drivers on New Zealand and southwest Pacific climate.  Overall, this work demonstrates that: a) the laminated sediments from Lake Ohau are varves and the formation of the annual stratigraphy is strongly controlled by lake hydrodynamics, in particular, thermal lake stratification; b) sediment stratigraphy reflects changes in austral warm period (December-May) inflow, enabling a highresolution reconstruction of hydroclimate over the last 1,350 years and; c) the generation of a paleocirculation index for the Western South Island points to significant changes between northerly or southerly dominated atmospheric conditions in southern New Zealand, particularly over the ‘Little Ice Age’ (1385-1710 AD). During this time, the strength of tropical teleconnections weakened and a strong negative phase SAM persisted. Comparison with high-resolution regional proxy records from Antarctica and the Central Pacific point to significant regional coherence with a strong negative phase SAM acting as a primary driver of the onset of Little Ice Age conditions across the South Pacific.</p>

scholarly journals Late-Holocene Climate Variability in Southern New Zealand: A reconstruction of regional climate from an annually laminated sediment sequence from Lake Ohau

2021 ◽  
Author(s):  
◽  
Heidi Anne Roop
Keyword(s):  
New Zealand ◽  
High Resolution ◽  
Little Ice Age ◽  
Ice Age ◽  
Negative Phase ◽  
Thin Sections ◽  
Southwest Pacific ◽  
Laminated Sediment ◽  
Annually Laminated Sediment ◽  
Instrumental Record

<p>This research aims to improve understanding of synoptic climate systems influencing southern New Zealand and document changes in the intensity and frequency of these systems beyond the historical record by analyzing a 1,350-year annually laminated sediment sequence recovered from Lake Ohau, South Island, New Zealand (44.234°S, 169.854°E). Climatological patterns originating in both the tropics (El-Niño-Southern Oscillation (ENSO), Interdecadal Pacific Oscillation (IPO)) and in the Antarctic (Southern Annular Mode (SAM)) influence year-to-year variability in New Zealand’s climate (e.g. temperature and precipitation). However, the range of natural variability of these systems in the southwest Pacific over time is poorly known because the instrumental record is short (~100 years). The high-resolution record from Lake Ohau offers a unique opportunity to investigate changes in regional hydrology and climate, and to also explore connections to large-scale climate patterns over the last millennium.  Hydrodynamic and hydroclimatic processes that influence and control the production, transport, and deposition of sediment within the Lake Ohau catchment are examined and constrained in order to develop a robust climate record. A key aim is to determine the role that meteorology and climate play in controlling sediment flux. The physical properties and facies of a 5.5-meter-long Lake Ohau sediment core are analyzed using thin-sections, high-resolution X-radiographs scans, and particle-size analyses. Time-series analysis is used to establish links between varve facies, hydroclimate variability and regional synoptic climate types over the instrumental record. Utilizing this climate-proxy relationship, inflow conditions are reconstructed over the last 1,350 years and compared with regional temperature reconstructions to generate a Western South Island paleo-atmospheric circulation index. Relationship between this paleocirculation index and other proxy reconstructions show significant variability in the relative forcing of tropical (ENSO) and Southern Hemisphere highlatitude (SAM) synoptic climate drivers on New Zealand and southwest Pacific climate.  Overall, this work demonstrates that: a) the laminated sediments from Lake Ohau are varves and the formation of the annual stratigraphy is strongly controlled by lake hydrodynamics, in particular, thermal lake stratification; b) sediment stratigraphy reflects changes in austral warm period (December-May) inflow, enabling a highresolution reconstruction of hydroclimate over the last 1,350 years and; c) the generation of a paleocirculation index for the Western South Island points to significant changes between northerly or southerly dominated atmospheric conditions in southern New Zealand, particularly over the ‘Little Ice Age’ (1385-1710 AD). During this time, the strength of tropical teleconnections weakened and a strong negative phase SAM persisted. Comparison with high-resolution regional proxy records from Antarctica and the Central Pacific point to significant regional coherence with a strong negative phase SAM acting as a primary driver of the onset of Little Ice Age conditions across the South Pacific.</p>

Greenhouses, hot water bottles, cycles and the future of New Zealand climate

2009 ◽  
pp. 61-67
Author(s):  
W.P. De Lange
Keyword(s):  
New Zealand ◽  
Thermal Energy ◽  
Infrared Radiation ◽  
Little Ice Age ◽  
Hot Water ◽  
Ice Age ◽  
The Sun ◽  
Weather Patterns ◽  
Time Periods ◽  
Almost All

The Greenhouse Effect acts to slow the escape of infrared radiation to space, and hence warms the atmosphere. The oceans derive almost all of their thermal energy from the sun, and none from infrared radiation in the atmosphere. The thermal energy stored by the oceans is transported globally and released after a range of different time periods. The release of thermal energy from the oceans modifies the behaviour of atmospheric circulation, and hence varies climate. Based on ocean behaviour, New Zealand can expect weather patterns similar to those from 1890-1922 and another Little Ice Age may develop this century.

scholarly journals Climate Variability in Central Europe during the Last 2500 Years Reconstructed from Four High-Resolution Multi-Proxy Speleothem Records

Geosciences ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 166
Author(s):  
Sarah Waltgenbach ◽  
Dana F. C. Riechelmann ◽  
Christoph Spötl ◽  
Klaus P. Jochum ◽  
Jens Fohlmeister ◽  
...  
Keyword(s):  
Trace Elements ◽  
High Resolution ◽  
Climate Variability ◽  
Little Ice Age ◽  
Medieval Warm Period ◽  
Warm Period ◽  
Ice Age ◽  
Cold Period ◽  
Cave System ◽  
Dark Ages

The Late Holocene was characterized by several centennial-scale climate oscillations including the Roman Warm Period, the Dark Ages Cold Period, the Medieval Warm Period and the Little Ice Age. The detection and investigation of such climate anomalies requires paleoclimate archives with an accurate chronology as well as a high temporal resolution. Here, we present 230Th/U-dated high-resolution multi-proxy records (δ13C, δ18O and trace elements) for the last 2500 years of four speleothems from Bunker Cave and the Herbstlabyrinth cave system in Germany. The multi-proxy data of all four speleothems show evidence of two warm and two cold phases during the last 2500 years, which coincide with the Roman Warm Period and the Medieval Warm Period, as well as the Dark Ages Cold Period and the Little Ice Age, respectively. During these four cold and warm periods, the δ18O and δ13C records of all four speleothems and the Mg concentration of the speleothems Bu4 (Bunker Cave) and TV1 (Herbstlabyrinth cave system) show common features and are thus interpreted to be related to past climate variability. Comparison with other paleoclimate records suggests a strong influence of the North Atlantic Oscillation at the two caves sites, which is reflected by warm and humid conditions during the Roman Warm Period and the Medieval Warm Period, and cold and dry climate during the Dark Ages Cold period and the Little Ice Age. The Mg records of speleothems Bu1 (Bunker Cave) and NG01 (Herbstlabyrinth) as well as the inconsistent patterns of Sr, Ba and P suggests that the processes controlling the abundance of these trace elements are dominated by site-specific effects rather than being related to supra-regional climate variability.

scholarly journals High‐resolution proglacial lake records of pre‐Little Ice Age glacier advance, northeast Greenland

Boreas ◽  
2018 ◽  
Vol 48 (3) ◽  
pp. 535-550 ◽  
Author(s):  
Kathryn Adamson ◽  
Timothy Lane ◽  
Matthew Carney ◽  
Thomas Bishop ◽  
Cathy Delaney
Keyword(s):  
High Resolution ◽  
Little Ice Age ◽  
Ice Age ◽  
Proglacial Lake ◽  
Glacier Advance

scholarly journals Estimating the longevity of glaciers in the Xinjiang region of the Tian Shan through observations of glacier area change since the Little Ice Age using high-resolution imagery

2020 ◽  
Vol 66 (257) ◽  
pp. 471-484
Author(s):  
Julia Liu ◽  
Daniel E. Lawson ◽  
Robert L. Hawley ◽  
Jonathan Chipman ◽  
Brian Tracy ◽  
...  
Keyword(s):  
High Resolution ◽  
Little Ice Age ◽  
Ice Age ◽  
Glacier Area ◽  
Glacier Surface ◽  
Relative Loss ◽  
High Resolution Imagery ◽  
High Resolution Satellite Imagery ◽  
Kaidu River ◽  
Tian Shan

AbstractGlacial retreat in response to warming climates in the arid Xinjiang region of northwestern China directly impacts downstream water resources available for local communities. We used high-resolution satellite imagery from 1969 to 2014 to delineate spatial changes in 54 active glaciers in the upper Kaidu River Basin in the Tian Shan as well as their past expanses during the Little Ice Age (LIA). We manually delineated their boundaries based on the interpretation of glacial, geomorphic and topographic features. From the total glacier surface area, we estimated glacier volume and mass. From 1969 to 2014, glacier area decreased by 10.1 ± 1.0 km2 (relative loss of 34.2 ± 3.5%) and mass by 1.025 ± 0.108 Gt (relative loss of 43 ± 4.6%). From the LIA maximum (est. 1586 CE) to 1969, relative losses were less (25.7 ± 4.3% area loss and 33.1 ± 5.7% mass loss). Our results indicate that glacier recession is accelerating over time and that the glaciers are currently losing over 1.5 times more relative area than elsewhere in the Tian Shan. Using linear and non-linear projections, we estimate that these glaciers may disappear between 2050 and 2150 CE if climatic warming continues at the same pace.

scholarly journals Climate and social change at the start of the Late Antique Little Ice Age

The Holocene ◽  
2020 ◽  
Vol 30 (11) ◽  
pp. 1643-1648 ◽  
Author(s):  
Peter N Peregrine
Keyword(s):  
Climate Change ◽  
High Resolution ◽  
Little Ice Age ◽  
Historical Data ◽  
Ice Age ◽  
Late Antique ◽  
Social Disruption ◽  
Epidemic Disease ◽  
Vulnerability To Climate Change ◽  
The Relationship

The Late Antique Little Ice Age, spanning the period from 536 CE to roughly 560 CE, saw temperatures in the Northern Hemisphere drop by a degree C in less than a decade. This rapid cooling is thought to have caused widespread famine, epidemic disease, and social disruption. The relationship between cooling and social disruption is examined here using a set of high-resolution climate and historical data. A significant link between cooling and social disruption is demonstrated, but it is also demonstrated that the link is highly variable, with some societies experiencing dramatic cooling changing very little, and others experiencing only slight cooling changing dramatically. This points to variation in vulnerability, and serves to establish the Late Antique Little Ice Age as a context within which naturalistic quasi-experiments on vulnerability to climate change might be conducted.

A revised Little Ice Age chronology of the Franz Josef Glacier, Westland, New Zealand

2004 ◽  
Vol 34 (4) ◽  
pp. 381-394 ◽  
Author(s):  
Krista M. McKinzey ◽  
Wendy Lawson ◽  
Dave Kelly ◽  
Alun Hubbard
Keyword(s):  
New Zealand ◽  
Little Ice Age ◽  
Ice Age

scholarly journals Distribución espacial y temporal de glaciares, glaciares cubiertos y glaciares rocosos durante la última deglaciación en el valle de La Bonaigua (Pirineo Central)

2020 ◽  
Vol 46 (2) ◽  
pp. 413-446
Author(s):  
J. Ventura-Roca
Keyword(s):  
High Resolution ◽  
Little Ice Age ◽  
Ice Age ◽  
Lidar Data ◽  
Forest Environment ◽  
Digital Elevation ◽  
Rock Glaciers ◽  
Elevation Model ◽  
Glacial Landforms ◽  
Central Pyrenees

The application of the paleogeographic method to the study of glacial landforms and rock glaciers allows their morphometric and sedimentological characterization, the establishment of a detailed morphostratigraphic sequence and a chronological proposal for the identified glacial phases. This study analyzes 86 landforms (57 glacial deposits, 21 rock glaciers and 8 protalus ramparts) in the Bonaigua Valley (Noguera Pallaresa Basin, Central Pyrenees), with special attention to the differentiation between debris-covered glaciers and rock glaciers. Other subjects studied concerning rock glaciers are: distinguish its glacial or periglacial origin; the possible current activity of some landforms, and the detection of rock glaciers located at low altitudes (in the current forest environment) through the use of high-resolution digital elevation model (2x2 m) from LIDAR data. The chronological hypothesis elaborated by correlation with other high Pyrenean valleys (with absolute ages available) includes 7 phases (6 glacial phases and 1 periglacial phase) in which co-exist and/or evolve, in a paraglacial dynamic, glaciers, debris-covered glaciers and rock glaciers, and that we temporarily place between the end of the Oldest Dryas and the Little Ice Age.

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