scholarly journals Detecting and Attributing External Influences on the Climate System: A Review of Recent Advances

2005 ◽  
Vol 18 (9) ◽  
pp. 1291-1314 ◽  
Author(s):  
Tim Barnett ◽  
Francis Zwiers ◽  
Gabriele Hengerl ◽  
Myles Allen ◽  
Tom Crowly ◽  
...  
Keyword(s):  
Large Scale ◽  
Climate Models ◽  
Large Fraction ◽  
Heat Content ◽  
Climate System ◽  
Past Century ◽  
External Forcing ◽  
The Past ◽  
External Influences ◽  
Scale Temperature

Abstract This paper reviews recent research that assesses evidence for the detection of anthropogenic and natural external influences on the climate. Externally driven climate change has been detected by a number of investigators in independent data covering many parts of the climate system, including surface temperature on global and large regional scales, ocean heat content, atmospheric circulation, and variables of the free atmosphere, such as atmospheric temperature and tropopause height. The influence of external forcing is also clearly discernible in reconstructions of hemispheric-scale temperature of the last millennium. These observed climate changes are very unlikely to be due only to natural internal climate variability, and they are consistent with the responses to anthropogenic and natural external forcing of the climate system that are simulated with climate models. The evidence indicates that natural drivers such as solar variability and volcanic activity are at most partially responsible for the large-scale temperature changes observed over the past century, and that a large fraction of the warming over the last 50 yr can be attributed to greenhouse gas increases. Thus, the recent research supports and strengthens the IPCC Third Assessment Report conclusion that “most of the global warming over the past 50 years is likely due to the increase in greenhouse gases.”

scholarly journals Global climatology and trends in convective environments from ERA5 and rawinsonde data

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Mateusz Taszarek ◽  
John T. Allen ◽  
Mattia Marchio ◽  
Harold E. Brooks
Keyword(s):  
Large Scale ◽  
Climate Models ◽  
Global Climate ◽  
Convective Available Potential Energy ◽  
Global Climate Models ◽  
Convective Precipitation ◽  
The Past ◽  
The Tropics ◽  
Rawinsonde Data

AbstractGlobally, thunderstorms are responsible for a significant fraction of rainfall, and in the mid-latitudes often produce extreme weather, including large hail, tornadoes and damaging winds. Despite this importance, how the global frequency of thunderstorms and their accompanying hazards has changed over the past 4 decades remains unclear. Large-scale diagnostics applied to global climate models have suggested that the frequency of thunderstorms and their intensity is likely to increase in the future. Here, we show that according to ERA5 convective available potential energy (CAPE) and convective precipitation (CP) have decreased over the tropics and subtropics with simultaneous increases in 0–6 km wind shear (BS06). Conversely, rawinsonde observations paint a different picture across the mid-latitudes with increasing CAPE and significant decreases to BS06. Differing trends and disagreement between ERA5 and rawinsondes observed over some regions suggest that results should be interpreted with caution, especially for CAPE and CP across tropics where uncertainty is the highest and reliable long-term rawinsonde observations are missing.

scholarly journals Climate model attractors: chaos, quasi-regularity and sensitivity to small perturbations of external forcing

2001 ◽  
Vol 8 (4/5) ◽  
pp. 201-209 ◽  
Author(s):  
V. P. Dymnikov ◽  
A. S. Gritsoun
Keyword(s):  
Climate Models ◽  
Climate Model ◽  
Global Attractors ◽  
Atmospheric Model ◽  
Climate System ◽  
External Forcing ◽  
Attractor Dimension ◽  
Small Perturbations ◽  
System Sensitivity ◽  
Fluctuation Dissipation

Abstract. In this paper we discuss some theoretical results obtained for climate models (theorems for the existence of global attractors and inertial manifolds, estimates of attractor dimension and Lyapunov exponents, symmetry property of Lyapunov spectrum). We define the conditions for "quasi-regular behaviour" of a climate system. Under these conditions, the system behaviour is subject to the Kraichnan fluctuation-dissipation relation. This fact allows us to solve the problem of determining a system's sensitivity to small perturbations to an external forcing. The applicability of the above approach to the analysis of the climate system sensitivity is verified numerically with the example of the two-layer quasi-geostrophic atmospheric model.

Genetic maps of the proximal half of chromosome arm 2L of Drosophila melanogaster

Genome ◽  
2007 ◽  
Vol 50 (2) ◽  
pp. 137-141 ◽  
Author(s):  
Sylvia Glen Levine ◽  
Suchot Sunday ◽  
Ruth E. Dörig ◽  
Beat Suter ◽  
Paul Lasko
Keyword(s):  
Drosophila Melanogaster ◽  
Large Scale ◽  
Research Community ◽  
Genetic Maps ◽  
Past Century ◽  
The Past ◽  
Proximal Half ◽  
Chromosome Arm ◽  
Physiologic Function ◽  
Complementation Groups

Drosophila mutants have played an important role in elucidating the physiologic function of genes. Large-scale projects have succeeded in producing mutations in a large proportion of Drosophila genes. Many mutant fly lines have also been produced through the efforts of individual laboratories over the past century. In an effort to make some of these mutants more useful to the research community, we systematically mapped a large number of mutations affecting genes in the proximal half of chromosome arm 2L to more precisely defined regions, defined by deficiency intervals, and, when possible, by individual complementation groups. To further analyze regions 36 and 39–40, we produced 11 new deficiencies with gamma irradiation, and we constructed 6 new deficiencies in region 30–33, using the DrosDel system. trans-heterozygous combinations of deficiencies revealed 5 additional functions, essential for viability or fertility.

scholarly journals De-schooling Well-being: Toward a Learning-Oriented Definition

2020 ◽  
Vol 3 (3) ◽  
pp. 452-469 ◽  
Author(s):  
Santiago Rincón-Gallardo
Keyword(s):  
Cultural Change ◽  
Large Scale ◽  
Well Being ◽  
Global South ◽  
Educational Systems ◽  
Past Century ◽  
Compulsory Schooling ◽  
Robust Learning ◽  
The Past ◽  
Grammar Of Schooling

Purpose: (1) Critique conventional schooling as detrimental to student well-being and learning. (2) Articulate an alternative that is more conducive to learning and well-being in classrooms, schools, and educational systems. Design/Approach/Methods: I review the historical functions of compulsory schooling, the main critiques to conventional schooling developed over the past century, emerging knowledge on the neuroscience of learning and well-being, and cases of large-scale pedagogical transformation from the Global South. Findings: I argue that conventional schooling is detrimental to well-being, that deep learning is a precursor of well-being, and that compulsory schooling is not designed to cultivate it. Well-being has to be de-schooled so that students thrive in schools: The grammar of schooling has to be replaced with the language of learning. This requires deep and widespread cultural change, and some movements of pedagogical renewal from the Global South offer important lessons on how to accomplish this. Originality/Value: Expanding the scope of existing debates about student well-being by questioning the assumption that compulsory schooling is inherently good and pointing out that unless the default culture of schooling is replaced with cultures of robust learning, student well-being efforts will simply reproduce the very problems they seek to solve.

Analysis of Recent Climatic Changes in the Arabian Gulf Region

1993 ◽  
Vol 20 (3) ◽  
pp. 223-226 ◽  
Author(s):  
Hassan A. Nasrallah ◽  
Robert C. Balling
Keyword(s):  
Climate Changes ◽  
Climate Models ◽  
Global Climate ◽  
Arabian Gulf ◽  
Past Century ◽  
Climatic Data ◽  
Gulf Region ◽  
The Past ◽  
The Face ◽  
Small Decline

Within the past few years, interest in climate change has increased dramatically in the face of the many apocalyptic predictions associated with the highly-popularized ‘greenhouse’ effect. Accordingly, scientists have produced many studies based on global, hemispheric, and regional, climatic data-bases. While most of the regional studies have been based on data from North America, Europe, and Australia, little research has been conducted in other areas of the world that have an equal (or greater) economic and climatic stake in the ‘greenhouse’ debate. In this investigation, we analyse the climatic records of the Arabian Gulf area in an attempt to identify recent changes that may or may not be related to any ‘greenhouse’ effects.The observed climate changes over the past century in the Arabian Gulf area include (a) an increase in temperature of 0.65°C, (b) warming in summer and little or no warming in winter, (c) no warming in the first 60 years of record but accelerated warming in the most recent 40 years, and (d) a small decline in precipitation. In many cases, the results are unlike those found in the analysis of Northern Hemispheric and/or global climate records. However, many of these observed climate changes in the Arabian Gulf area are broadly consistent with 2×CO2 predictions from various numerical climate models. We hope that the analyses presented in this investigation will aid decisionmakers in their difficult policymaking activities.

scholarly journals The construction of a Central Netherlands temperature

2010 ◽  
Vol 6 (6) ◽  
pp. 2517-2555 ◽  
Author(s):  
G. van der Schrier ◽  
A. van Ulden ◽  
G. J. van Oldenborgh
Keyword(s):  
Time Series ◽  
The Netherlands ◽  
Large Scale ◽  
Climate Models ◽  
Temperature Series ◽  
Homogeneity Analysis ◽  
Temperature Changes ◽  
Long Time Series ◽  
Scale Temperature ◽  
Long Time

Abstract. The Central Netherlands Temperature (CNT) is a monthly daily mean temperature series constructed from homogenised time series from the centre of the Netherlands. The purpose of this series is to offer a homogeneous time series representative of a larger area to study large-scale temperature changes. It will also facilitate a comparison with climate models, which resolve similar scales. From 1906 onwards, temperature measurements in the Netherlands have been sufficiently standardised to construct a high-quality series. Long time series have been constructed by merging nearby stations, using the overlap to calibrate the differences. These long time series and a few time series of only a few decades in length, have been subjected to a homogeneity analysis in which significant breaks and artificial trends have been corrected. Many of the detected breaks correspond to changes in the observations that are documented in the station metadata. This version of the CNT, to which we attach the version number 1.1, is constructed as the unweighted average of four stations (De Bilt, Winterswijk/Hupsel, Oudenbosch/Gilze-Rijen and Gemert/Volkel) with the stations Eindhoven and Deelen added from 1951 and 1958 respectively onwards.

scholarly journals A synthesis of the Antarctic surface mass balance during the last 800 yr

2013 ◽  
Vol 7 (1) ◽  
pp. 303-319 ◽  
Author(s):  
M. Frezzotti ◽  
C. Scarchilli ◽  
S. Becagli ◽  
M. Proposito ◽  
S. Urbini
Keyword(s):  
Mass Balance ◽  
Large Scale ◽  
Climate Models ◽  
Wave Train ◽  
Global Climate Models ◽  
Surface Mass Balance ◽  
Blowing Snow ◽  
High Accumulation ◽  
Surface Mass ◽  
The Past

Abstract. Global climate models suggest that Antarctic snowfall should increase in a warming climate and mitigate rises in the sea level. Several processes affect surface mass balance (SMB), introducing large uncertainties in past, present and future ice sheet mass balance. To provide an extended perspective on the past SMB of Antarctica, we used 67 firn/ice core records to reconstruct the temporal variability in the SMB over the past 800 yr and, in greater detail, over the last 200 yr. Our SMB reconstructions indicate that the SMB changes over most of Antarctica are statistically negligible and that the current SMB is not exceptionally high compared to the last 800 yr. High-accumulation periods have occurred in the past, specifically during the 1370s and 1610s. However, a clear increase in accumulation of more than 10% has occurred in high SMB coastal regions and over the highest part of the East Antarctic ice divide since the 1960s. To explain the differences in behaviour between the coastal/ice divide sites and the rest of Antarctica, we suggest that a higher frequency of blocking anticyclones increases the precipitation at coastal sites, leading to the advection of moist air in the highest areas, whereas blowing snow and/or erosion have significant negative impacts on the SMB at windy sites. Eight hundred years of stacked records of the SMB mimic the total solar irradiance during the 13th and 18th centuries. The link between those two variables is probably indirect and linked to a teleconnection in atmospheric circulation that forces complex feedback between the tropical Pacific and Antarctica via the generation and propagation of a large-scale atmospheric wave train.

Eastern Mediterranean Drying: Projected Changes in Dynamics and Thermodynamics and Their Relation to Large-Scale Processes

2020 ◽  
Author(s):  
Eilat Elbaum ◽  
Chaim Garfinkel ◽  
Ori Adam ◽  
Efrat Morin
Keyword(s):  
Large Scale ◽  
Eastern Mediterranean ◽  
Coupled Model ◽  
Past Century ◽  
The Past ◽  
Intercomparison Project ◽  
The Individual ◽  
Projected Changes ◽  
Precipitation Changes

<p>Observations from the past century and projections for the end of this century exhibit a decrease in precipitation over the Eastern Mediterranean Sea and surrounding land areas, but the magnitude of the expected drying is unknown. Changes in precipitation are controlled by both thermodynamic (moist) and dynamic (dry) processes, but the relative contributions of these processes, in particular on regional scales, is not well understood. Previous studies have analyzed the ability of the fifth phase of the Coupled Model Intercomparison Project (CMIP5) multi-model mean to represent the spatial and seasonal patterns of the Mediterranean hydroclimate. A wide spread exists among the individual models, which can be exploited to better understand the factors controlling future climate. Garfinkel et al. (2020)<sup>[i]</sup> found that large-scale mechanisms contribute about 50% of the model spread in Eastern Mediterranean drying. This study further explores the variance across models in projected changes of the moisture budget by decomposing them into mean dynamic, mean thermodynamic and transient components. These components are then related to the variance across models in projected large-scale processes. Through these analyses, uncertainties regarding future changes in precipitation can be reduced.</p><p><sup>[i]</sup> Garfinkel, C. I. et al. (2020) ‘The role of zonally averaged climate change in contributing to inter-model spread in CMIP5 predicted local precipitation changes’, Journal of Climate, 33, pp. 1141–1154. doi: 10.1175/JCLI-D-19-0232.1.</p>

scholarly journals Fifth IPCC Assessment Report Now Out

2014 ◽  
Vol 21 (1) ◽  
pp. 9-27 ◽  
Author(s):  
Zbigniew W. Kundzewicz
Keyword(s):  
Climate Change ◽  
Physical Science ◽  
Climate Models ◽  
Climate System ◽  
Intergovernmental Panel ◽  
Response Options ◽  
Assessment Report ◽  
The Past ◽  
Working Groups ◽  
Synthesis Report

Abstract The Fifth Assessment Report (AR5) of the Intergovernmental Panel on Climate Change (IPCC) is now available. It provides policymakers with an assessment of information on climate change, its impacts and possible response options (adaptation and mitigation). Summaries for policymakers of three reports of IPCC working groups and of the Synthesis Report have now been approved by IPCC plenaries. This present paper reports on the most essential findings in AR5. It briefly informs on the contents of reports of all IPCC working groups. It discusses the physical science findings, therein observed changes (ubiquitous warming, shrinking cryosphere, sea level rise, changes in precipitation and extremes, and biogeochemical cycles). It deals with the drivers of climate change, progress in climate system understanding (evaluation of climate models, quantification of climate system responses), and projections for the future. It reviews impacts, adaptation and vulnerability, including observed changes, key risks, key reasons for concern, sectors and systems, and managing risks and building resilience. Finally, mitigation of climate change is discussed, including greenhouse gas emissions in the past, present and future, and mitigation in sectors. It is hoped that the present article will encourage the readership of this journal to dive into the AR5 report that provides a wealth of useful information.

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