Separating effects of climatic drivers and biotic feedbacks on seasonal plankton dynamics: no sign of trophic mismatch

AbstractAsian Monsoon rainfall supports the livelihood of billions of people, yet the relative importance of different drivers remains an issue of great debate. Here, we present 30 million-year model-based reconstructions of Indian summer monsoon and South East Asian monsoon rainfall at millennial resolution. We show that precession is the dominant direct driver of orbital variability, although variability on obliquity timescales is driven through the ice sheets. Orographic development dominated the evolution of the South East Asian monsoon, but Indian summer monsoon evolution involved a complex mix of contributions from orography (39%), precession (25%), atmospheric CO2 (21%), ice-sheet state (5%) and ocean gateways (5%). Prior to 15 Ma, the Indian summer monsoon was broadly stable, albeit with substantial orbital variability. From 15 Ma to 5 Ma, strengthening was driven by a combination of orography and glaciation, while closure of the Panama gateway provided the prerequisite for the modern Indian summer monsoon state through a strengthened Atlantic meridional overturning circulation.

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The effect of a sharp pycnocline on plankton dynamics in a freshwater influenced Norwegian fjord

Ophelia ◽

10.1080/00785236.2002.10409495 ◽

2002 ◽

Vol 56 (3) ◽

pp. 135-160 ◽

Cited By ~ 8

Author(s):

Christian Marc Andersen ◽

Torkel Gissel Nielsen

Keyword(s):

Plankton Dynamics ◽

Norwegian Fjord

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Effects of Climatic Drivers and Teleconnections on Late 20th Century Trends in Spring Freshet of Four Major Arctic-Draining Rivers

Water ◽

10.3390/w13020179 ◽

2021 ◽

Vol 13 (2) ◽

pp. 179

Author(s):

Roxanne Ahmed ◽

Terry Prowse ◽

Yonas Dibike ◽

Barrie Bonsal

Keyword(s):

Arctic Ocean ◽

Large Scale ◽

Southern Oscillation ◽

Rate Of Change ◽

The Arctic ◽

Late 20Th Century ◽

Basin Scale ◽

The Arctic Ocean ◽

Spring Freshet ◽

Climatic Drivers

Spring freshet is the dominant annual discharge event in all major Arctic draining rivers with large contributions to freshwater inflow to the Arctic Ocean. Research has shown that the total freshwater influx to the Arctic Ocean has been increasing, while at the same time, the rate of change in the Arctic climate is significantly higher than in other parts of the globe. This study assesses the large-scale atmospheric and surface climatic conditions affecting the magnitude, timing and regional variability of the spring freshets by analyzing historic daily discharges from sub-basins within the four largest Arctic-draining watersheds (Mackenzie, Ob, Lena and Yenisei). Results reveal that climatic variations closely match the observed regional trends of increasing cold-season flows and earlier freshets. Flow regulation appears to suppress the effects of climatic drivers on freshet volume but does not have a significant impact on peak freshet magnitude or timing measures. Spring freshet characteristics are also influenced by El Niño-Southern Oscillation, the Pacific Decadal Oscillation, the Arctic Oscillation and the North Atlantic Oscillation, particularly in their positive phases. The majority of significant relationships are found in unregulated stations. This study provides a key insight into the climatic drivers of observed trends in freshet characteristics, whilst clarifying the effects of regulation versus climate at the sub-basin scale.

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Respiration of Russian soils: climatic drivers and response to climate change

The Science of The Total Environment ◽

10.1016/j.scitotenv.2021.147314 ◽

2021 ◽

pp. 147314

Author(s):

Liudmila Mukhortova ◽

Dmitry Schepaschenko ◽

Elena Moltchanova ◽

Anatoly Shvidenko ◽

Nikolay Khabarov ◽

...

Keyword(s):

Climate Change ◽

Climatic Drivers

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A millennium-long perspective on high-elevation pine recruitment in the Spanish central Pyrenees

Canadian Journal of Forest Research ◽

10.1139/cjfr-2018-0025 ◽

2018 ◽

Vol 48 (9) ◽

pp. 1108-1113 ◽

Cited By ~ 7

Author(s):

Gabriel Sangüesa-Barreda ◽

J. Julio Camarero ◽

Jan Esper ◽

J. Diego Galván ◽

Ulf Büntgen

Keyword(s):

Ring Width ◽

High Elevation ◽

Upward Migration ◽

Scale Temperature ◽

Decadal Scale ◽

History Of ◽

Climatic Drivers ◽

Individual Trees ◽

Central Pyrenees

Long-term fluctuations in forest recruitment, at time scales well beyond the life-span of individual trees, can be related to climate changes. The underlying climatic drivers are, however, often understudied. Here, we present the recruitment history of a high-elevation mountain pine (Pinus uncinata Ram.) forest in the Spanish central Pyrenees throughout the last millennium. A total of 1108 ring-width series translated into a continuous chronology from 924 to 2014 CE, which allowed estimated germination dates of 470 trees to be compared against decadal-scale temperature variability. High recruitment intensity mainly coincided with relatively warm periods in the early 14th, 15th, 19th, and 20th centuries, whereas cold phases during the mid-17th, early 18th, and mid-19th centuries overlapped with generally low recruitment rates. In revealing the importance of prolonged warm conditions for high-elevation pine recruitment in the Pyrenees, this study suggests increased densification and even possible upward migration of tree-line ecotones under predicted global warming.

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Digital holographic video for studies of plankton dynamics

Russian Physics Journal ◽

10.1007/s11182-011-9500-z ◽

2011 ◽

Vol 53 (8) ◽

pp. 857-866 ◽

Cited By ~ 14

Author(s):

V. V. Dyomin ◽

A. S. Olshukov ◽

E. V. Dzyuba

Keyword(s):

Plankton Dynamics

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Flowering, floral visitors and climatic drivers of reproductive phenology of two endangered magnolias from neotropical A ndean forests

Plant Species Biology ◽

10.1111/1442-1984.12351 ◽

2021 ◽

Author(s):

Marcela Serna‐González ◽

Ligia E. Urrego‐Giraldo ◽

Juan P. Santa‐Ceballos ◽

Hiroshi Suzuki‐Azuma

Keyword(s):

Reproductive Phenology ◽

Climatic Drivers ◽

Floral Visitors

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Correlates of Annual Stopover Counts in Two Species of Arctic-Breeding Shorebirds: Roles of Local, Breeding, and Climatic Drivers

Waterbirds ◽

10.1675/063.044.0102 ◽

2021 ◽

Vol 44 (1) ◽

Author(s):

David D. Hope ◽

Anna Drake ◽

Daniel Shervill ◽

Moira J. F. Lemon ◽

Mark C. Drever

Keyword(s):

Local Breeding ◽

Climatic Drivers

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Detecting Climate Fingerprints in Southern Ocean Carbon using a Biogeochemical Ocean Model

10.5194/egusphere-egu21-11116 ◽

2021 ◽

Author(s):

Rebecca Wright ◽

Corinne Le Quéré ◽

Erik Buitenhuis ◽

Dorothee Bakker

Keyword(s):

Climate Change ◽

Climate Variability ◽

Southern Ocean ◽

Observational Data ◽

Ecosystem Dynamics ◽

Global Ocean ◽

Subsurface Waters ◽

Climatic Drivers ◽

Ocean Carbon ◽

And Storage

The Southern Ocean plays an important role in the uptake, transport and storage of carbon by the global oceans. These properties are dominated by the response to the rise in anthropogenic CO2 in the atmosphere, but they are modulated by climate variability and climate change. Here we explore the effect of climate variability and climate change on ocean carbon uptake and storage in the Southern Ocean. We assess the extent to which climate change may be distinguishable from the anthropogenic CO2 signal and from the natural background variability. We use a combination of biogeochemical ocean modelling and observations from the GLODAPv2020 database to detect climate fingerprints in dissolved inorganic carbon (DIC).We conduct an ensemble of hindcast model simulations of the period 1920-2019, using a global ocean biogeochemical model which incorporates plankton ecosystem dynamics based on twelve plankton functional types. We use the model ensemble to isolate the changes in DIC due to rising anthropogenic CO2 alone and the changes due to climatic drivers (both climate variability and climate change), to determine their relative roles in the emerging total DIC trends and patterns. We analyse these DIC trends for a climate fingerprint over the past four decades, across spatial scales from the Southern Ocean, to basin level and down to regional ship transects. Highly sampled ship transects were extracted from GLODAPv2020 to obtain locations with the maximum spatiotemporal coverage, to reduce the inherent biases in patchy observational data. Model results were sampled to the ship transects to compare the climate fingerprints directly to the observational data.Model results show a substantial change in DIC over a 35-year period, with a range of more than +/- 30 &#181;mol/L. In the surface ocean, both anthropogenic CO2 and climatic drivers act to increase DIC concentration, with the influence of anthropogenic CO2 dominating at lower latitudes and the influence of climatic drivers dominating at higher latitudes. In the deep ocean, the anthropogenic CO2 generally acts to increase DIC except in the subsurface waters at lower latitudes, while climatic drivers act to decrease DIC concentration. The combined fingerprint of anthropogenic CO2 and climatic drivers on DIC concentration is for an increasing trend at the surface and decreasing trends in low latitude subsurface waters. Preliminary comparison of the model fingerprints to observational ship transects will also be presented.

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