Century-scale solar variability and Alaskan temperature change over the past millennium

Abstract. We examine the characteristics (amplitude and phase) of the temporal variation in the rates of global-mean surface temperature change during the past millennium. The study was conducted by applying 20-, 30-, and 50-yr sliding windows to the observations of recent century and reconstructions of earlier times. The analysis focuses on the characteristics of the 20th century within the context of the millennium as well as their sensitivity to the low frequency variability of sea surface temperature (SST) and time scales. On 20-yr time scale, comparable rates to that of the 20th century in both amplitude and phase occur in earlier nine centuries. The peak in the amplitude of rates in the 20th century on 30-yr time scale, although is not the largest during the past millennium, but is the most persistent. On 50-yr time scale, the 20th century warming rates are the highest and the most persistent during the past millennium. The results also indicate that although the SST variability does not affect much the amplitude of the rates, but the phases is quite different, thus highlighting the importance of the role of oceans in affecting the rates. We also analyzed the characteristics from global climate model (1000–1999 AD) simulations with different climate (solar, volcanic, and greenhouse gases) forcing. Except for the one driven by the solar forcing, other forcing simulates similar amplitudes as the observed ones. However, only greenhouse gases (GHG) forcing can reproduce the persistent high warming rates of the 20th century.

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Rates of global temperature change during the past millennium

Climate Research ◽

10.3354/cr01159 ◽

2013 ◽

Vol 57 (1) ◽

pp. 11-18 ◽

Cited By ~ 3

Author(s):

C Shen ◽

WC Wang ◽

G Zeng ◽

Y Peng ◽

Y Xu

Keyword(s):

Temperature Change ◽

Global Temperature ◽

The Past ◽

Global Temperature Change ◽

Past Millennium

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HURRICANE FREQUENCY NEAR CHESAPEAKE BAY DURING THE PAST MILLENNIUM

10.1130/abs/2019ne-328312 ◽

2019 ◽

Author(s):

Michael Toomey ◽

◽

Nicole D'Entremont ◽

Emma Armstrong ◽

Thomas Cronin ◽

...

Keyword(s):

Chesapeake Bay ◽

The Past ◽

Past Millennium

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Comparison of the HYDE cropland data over the past millennium with regional historical evidence from Germany

Regional Environmental Change ◽

10.1007/s10113-020-01735-1 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Diyang Zhang ◽

Xiuqi Fang ◽

Liang Emlyn Yang

Keyword(s):

Historical Evidence ◽

The Past ◽

Past Millennium

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Conceptualizing histories of multispecies entanglements: Ancient pathogen genomics and the case of Borrelia recurrentis

Journal of Social Archaeology ◽

10.1177/1469605321993942 ◽

2021 ◽

pp. 146960532199394

Author(s):

Venla Oikkonen

Keyword(s):

East Africa ◽

Ancient Dna ◽

Relapsing Fever ◽

Borrelia Recurrentis ◽

The Past ◽

Cultural Implications ◽

Past Millennium

This article explores the conceptual and cultural implications of using pathogen ancient DNA (aDNA) collected in archaeological contexts to understand the past. More specifically, it examines ancient pathogen genomics as a way of conceptualizing multispecies entanglements. The analysis focuses on the 2018 sequencing of Borrelia recurrentis bacteria retrieved from a medieval graveyard in Oslo, Norway. B. recurrentis is associated with louse-borne relapsing fever (LBRF), known to have killed several million people in Europe during the past millennium, and it is still encountered in parts of East Africa. The article demonstrates that while aDNA research often foregrounds multispecies entanglements, its epistemic tools cannot easily address the ontological blurriness of pathogens and their embeddedness in vibrant material processes. The article draws on feminist posthumanities work on microbes and materiality to highlight conceptual openings that a theorization of ancient pathogens could engender.

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Climate and environmental changes during the past millennium in central western Guizhou, China as recorded by Stalagmite ZJD-21

Journal of Asian Earth Sciences ◽

10.1016/j.jseaes.2011.01.001 ◽

2011 ◽

Vol 40 (6) ◽

pp. 1111-1120 ◽

Cited By ~ 27

Author(s):

Tz-Shing Kuo ◽

Zi-Qi Liu ◽

Hong-Chun Li ◽

Nai-Jung Wan ◽

Chuan-Chou Shen ◽

...

Keyword(s):

Environmental Changes ◽

The Past ◽

Western Guizhou ◽

Past Millennium

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Supporting Restoration Decisions through Integration of Tree-Ring and Modeling Data: Reconstructing Flow and Salinity in the San Francisco Estuary over the Past Millennium

Water ◽

10.3390/w13152139 ◽

2021 ◽

Vol 13 (15) ◽

pp. 2139

Author(s):

Paul H. Hutton ◽

David M. Meko ◽

Sujoy B. Roy

Keyword(s):

San Francisco ◽

Tree Ring ◽

San Francisco Estuary ◽

Salinity Intrusion ◽

Estuarine Ecosystem ◽

Freshwater Flow ◽

The Past ◽

Decadal Scale ◽

Tree Ring Data ◽

Past Millennium

This work presents updated reconstructions of watershed runoff to San Francisco Estuary from tree-ring data to AD 903, coupled with models relating runoff to freshwater flow to the estuary and salinity intrusion. We characterize pre-development freshwater flow and salinity conditions in the estuary over the past millennium and compare this characterization with contemporary conditions to better understand the magnitude and seasonality of changes over this time. This work shows that the instrumented flow record spans the range of runoff patterns over the past millennium (averaged over 5, 10, 20 and 100 years), and thus serves as a reasonable basis for planning-level evaluations of historical hydrologic conditions in the estuary. Over annual timescales we show that, although median freshwater flow to the estuary has not changed significantly, it has been more variable over the past century compared to pre-development flow conditions. We further show that the contemporary period is generally associated with greater spring salinity intrusion and lesser summer–fall salinity intrusion relative to the pre-development period. Thus, salinity intrusion in summer and fall months was a common occurrence under pre-development conditions and has been moderated in the contemporary period due to the operations of upstream reservoirs, which were designed to hold winter and spring runoff for release in summer and fall. This work also confirms a dramatic decadal-scale hydrologic shift in the watershed from very wet to very dry conditions during the late 19th and early 20th centuries; while not unprecedented, these shifts have been seen only a few times in the past millennium. This shift resulted in an increase in salinity intrusion in the first three decades of the 20th century, as documented through early records. Population growth and extensive watershed modification during this period exacerbated this underlying hydrologic shift. Putting this shift in the context of other anthropogenic drivers is important in understanding the historical response of the estuary and in setting salinity targets for estuarine restoration. By characterizing the long-term behavior of San Francisco Estuary, this work supports decision-making in the State of California related to flow and salinity management for restoration of the estuarine ecosystem.

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