1
|
Zhu F, Emile-Geay J, Anchukaitis KJ, McKay NP, Stevenson S, Meng Z. A pseudoproxy emulation of the PAGES 2k database using a hierarchy of proxy system models. Sci Data 2023; 10:624. [PMID: 37709805 PMCID: PMC10502095 DOI: 10.1038/s41597-023-02489-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Accepted: 08/18/2023] [Indexed: 09/16/2023] Open
Abstract
Paleoclimate reconstructions are now integral to climate assessments, yet the consequences of using different methodologies and proxy data require rigorous benchmarking. Pseudoproxy experiments (PPEs) provide a tractable and transparent test bed for evaluating climate reconstruction methods and their sensitivity to aspects of real-world proxy networks. Here we develop a dataset that leverages proxy system models (PSMs) for this purpose, which emulates the essential physical, chemical, biological, and geological processes that translate climate signals into proxy records, making these synthetic proxies more relevant to the real world. We apply a suite of PSMs to emulate the widely-used PAGES 2k dataset, including realistic spatiotemporal sampling and error structure. A hierarchical approach allows us to produce many variants of this base dataset, isolating the impact of sampling bias in time and space, representation error, sampling error, and other assumptions. Combining these various experiments produces a rich dataset ("pseudoPAGES2k") for many applications. As an illustration, we show how to conduct a PPE with this dataset based on emerging climate field reconstruction techniques.
Collapse
Affiliation(s)
- Feng Zhu
- Climate and Global Dynamics Laboratory, National Center for Atmospheric Research, Boulder, CO, USA.
| | - Julien Emile-Geay
- Department of Earth Sciences, University of Southern California, Los Angeles, CA, USA
| | - Kevin J Anchukaitis
- Laboratory of Tree-Ring Research, University of Arizona, Tucson, AZ, USA
- School of Geography, Development, and Environment, University of Arizona, Tucson, AZ, USA
| | - Nicholas P McKay
- School of Earth and Sustainability, Northern Arizona University, Flagstaff, AZ, USA
| | - Samantha Stevenson
- Bren School of Environmental Science and Management, University of California, Santa Barbara, Santa Barbara, CA, USA
| | - Zilu Meng
- Department of Atmospheric Sciences, University of Washington, Seattle, WA, USA
| |
Collapse
|
2
|
Reboita MS, Ambrizzi T, Crespo NM, Dutra LMM, Ferreira GWDS, Rehbein A, Drumond A, da Rocha RP, Souza CAD. Impacts of teleconnection patterns on South America climate. Ann N Y Acad Sci 2021; 1504:116-153. [PMID: 33914367 DOI: 10.1111/nyas.14592] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2020] [Revised: 02/16/2021] [Accepted: 02/24/2021] [Indexed: 11/29/2022]
Abstract
Oceanic heat sources disturb the atmosphere, which, to come back to its initial state, disperses waves. These waves affect the climate in remote regions, characterizing the teleconnection patterns. In this study, we describe eight teleconnection patterns that affect South America climate: the El Niño-Southern Oscillation (ENSO), the Pacific Decadal Oscillation (PDO), the Atlantic Multidecadal Oscillation (AMO), the Tropical Atlantic Dipole (TAD), the South Atlantic Dipole (SAD), the Southern Annular Mode (SAM), the Madden-Julian Oscillation (MJO), and the Indian Ocean Dipole (IOD). Precipitation and winds at 850-hPa anomalies, considering these teleconnection patterns in ENSO neutral periods, are also presented. Overall, southeastern South America and the north sector of the North and Northeast regions of Brazil are the most affected areas by the teleconnection patterns. In general, there is a precipitation dipole pattern between these regions during each teleconnection pattern.
Collapse
Affiliation(s)
| | - Tércio Ambrizzi
- Departamento de Ciências Atmosféricas, Instituto de Astronomia, Geofísica e Ciências Atmosféricas, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Natália Machado Crespo
- Departamento de Ciências Atmosféricas, Instituto de Astronomia, Geofísica e Ciências Atmosféricas, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Lívia Márcia Mosso Dutra
- Departamento de Ciências Atmosféricas, Instituto de Astronomia, Geofísica e Ciências Atmosféricas, Universidade de São Paulo, São Paulo, SP, Brazil
| | | | - Amanda Rehbein
- Departamento de Ciências Atmosféricas, Instituto de Astronomia, Geofísica e Ciências Atmosféricas, Universidade de São Paulo, São Paulo, SP, Brazil
| | - Anita Drumond
- Instituto de Ciências Ambientais, Químicas e Farmacêuticas, Universidade Federal de São Paulo, Diadema, SP, Brazil
| | - Rosmeri Porfírio da Rocha
- Departamento de Ciências Atmosféricas, Instituto de Astronomia, Geofísica e Ciências Atmosféricas, Universidade de São Paulo, São Paulo, SP, Brazil
| | | |
Collapse
|
3
|
Southern Hemisphere Pressure Relationships during the 20th Century—Implications for Climate Reconstructions and Model Evaluation. GEOSCIENCES 2019. [DOI: 10.3390/geosciences9100413] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The relationship between Southern Hemisphere middle and high-latitude regions has made it possible to generate observationally-based Antarctic pressure reconstructions throughout the 20th century, even though routinely collected observations for this continent only began around 1957. While nearly all reconstructions inherently assume stability in these relationships through time and in the absence of direct observations, this stationarity constraint can be fully tested in a model setting. Seasonal pressure reconstructions based on the principal component regression (PCR) method spanning 1905–2013 are done entirely within the framework of the Community Atmospheric version 5 (CAM5) model in this study in order to evaluate this assumption, test the robustness of the PCR procedure for Antarctic pressure reconstructions and to evaluate the CAM5 model. Notably, the CAM5 reconstructions outperformed the observationally-based reconstruction in every season except the austral summer. Other tests indicate that relationships between Antarctic pressure and pressure across the Southern Hemisphere remain stable throughout the 20th century in CAM5. In contrast, 20th century reanalyses all display marked changes in mid-to-high latitude pressure relationships in the early 20th century. Overall, comparisons indicate both the CAM5 model and the pressure reconstructions evaluated here are reliable estimates of Antarctic pressure throughout the 20th century, with the largest differences between the two resulting from differences in the underlying reconstruction predictor networks and not from changes in the model experiments.
Collapse
|
4
|
A new species of the cheilostome bryozoan Chiastosella in the Southern Ocean, past and present. Polar Biol 2014. [DOI: 10.1007/s00300-014-1478-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
5
|
Moy CM, Moreno PI, Dunbar RB, Kaplan MR, Francois JP, Villalba R, Haberzettl T. Climate Change in Southern South America During the Last Two Millennia. PAST CLIMATE VARIABILITY IN SOUTH AMERICA AND SURROUNDING REGIONS 2009. [DOI: 10.1007/978-90-481-2672-9_15] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
|
6
|
Fischer MJ, Treble PC. Calibrating climate-δ18O regression models for the interpretation of high-resolution speleothemδ18O time series. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2007jd009694] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
7
|
Monaghan AJ, Bromwich DH, Chapman W, Comiso JC. Recent variability and trends of Antarctic near-surface temperature. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2007jd009094] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
8
|
Schneider DP, Noone DC. Spatial covariance of water isotope records in a global network of ice cores spanning twentieth-century climate change. ACTA ACUST UNITED AC 2007. [DOI: 10.1029/2007jd008652] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
9
|
Miller RL, Schmidt GA, Shindell DT. Forced annular variations in the 20th century Intergovernmental Panel on Climate Change Fourth Assessment Report models. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2005jd006323] [Citation(s) in RCA: 294] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|