Browse
Abstract
Before the satellite era, global sea-level reconstructions depend on tide-gauge records and in-situ hydrographic observations. However, the available global mean sea-level (GMSL) reconstructions, using different methods, indicate a spread in sea-level trend over 1900-2008 (1.3ā¼2.0 mm yrā1). With better understanding of the causes of sea-level change, here we implement an improved sea-level reconstruction, building upon Church and White (2011), and including three additional factors: the sea-level fingerprints, the sterodynamic sea level (SDSL) climate change patterns and more complete local vertical land motion (VLM) estimates. The trend of new GMSL reconstruction is 1.6 Ā± 0.2 mm yrā1 (90% confidence level) over 1900-2019, consistent with the sum of observation-based sea-level contributions of 1.5 Ā± 0.2 mm yrā1. The lower trend from the new reconstruction compared with the earlier Church and White (2011) result is mainly due to the updated VLM correction. The inclusion of sea-level fingerprints and SDSL climate change patterns are the dominant contributors for the improved skill of regional reconstruction. Despite GMSL budget closure in terms of long-term trend since 1900, our study shows discrepancies between the trends from available GMSL reconstructions and the sum of independent observation-based contributions over different periods in the 20th century, e.g., the discrepancy at the beginning of the 20th century, which could be related to possible bias in the land ice component estimate. The reconstruction methodology developed here, as tested with synthetic sea-level fields, could provide a promising way to identify potential biases in the individual sea-level components constrained by available global tide-gauge observations.
Abstract
Before the satellite era, global sea-level reconstructions depend on tide-gauge records and in-situ hydrographic observations. However, the available global mean sea-level (GMSL) reconstructions, using different methods, indicate a spread in sea-level trend over 1900-2008 (1.3ā¼2.0 mm yrā1). With better understanding of the causes of sea-level change, here we implement an improved sea-level reconstruction, building upon Church and White (2011), and including three additional factors: the sea-level fingerprints, the sterodynamic sea level (SDSL) climate change patterns and more complete local vertical land motion (VLM) estimates. The trend of new GMSL reconstruction is 1.6 Ā± 0.2 mm yrā1 (90% confidence level) over 1900-2019, consistent with the sum of observation-based sea-level contributions of 1.5 Ā± 0.2 mm yrā1. The lower trend from the new reconstruction compared with the earlier Church and White (2011) result is mainly due to the updated VLM correction. The inclusion of sea-level fingerprints and SDSL climate change patterns are the dominant contributors for the improved skill of regional reconstruction. Despite GMSL budget closure in terms of long-term trend since 1900, our study shows discrepancies between the trends from available GMSL reconstructions and the sum of independent observation-based contributions over different periods in the 20th century, e.g., the discrepancy at the beginning of the 20th century, which could be related to possible bias in the land ice component estimate. The reconstruction methodology developed here, as tested with synthetic sea-level fields, could provide a promising way to identify potential biases in the individual sea-level components constrained by available global tide-gauge observations.
Abstract
The North Atlantic Ocean forcings are considered an important origin of the North Atlantic atmospheric multidecadal variability. Here, we reveal the energetics mechanisms of the phenomenon using the perturbation potential energy (PPE) theory. Supporting the previous model studies, a cyclic pattern involving the Atlantic multidecadal oscillation (AMO) and the North Atlantic tripole (NAT) is observed: positive AMO phase (AMO+) ā NATā ā AMOā ā NAT+, with a phase lag of approximately 15ā20 years. An atmospheric mode characterized by basinscale sea level pressure anomaly in the North Atlantic is associated with the AMO, which is termed the North Atlantic uniformity (NAU). The AMO+ induces positive uniform PPE anomalies over the ocean through precipitation heating, leading to decreased energy conversion to perturbation kinetic energy (PKE) and a large-scale anomalous cyclone. For the NAT+, tripolar precipitation anomalies result in tripolar PPE anomalies. Anomalous energy conversions occur where the PPE anomaly gradient is large, explained by an energy balance derived from thermal wind relationship. The PKE around 15Ā° and 50Ā°N (25Ā° and 75Ā°N) increases (decreases), forming the anomalous anticyclone and cyclone at subtropical and subpolar regions, respectively, known as the North Atlantic Oscillation (NAO). The reverse holds for the NATā and AMOā. As the phases of the ocean modes alternate, the energetics induce the NAUā, NAOā, NAU+, and NAO+ sequentially. In the multidecadal cycle, the accumulated energetics process is related to delayed effect, and the difference in variance explanation between the NAU and NAO is attributed to the feedback mechanisms.
Significance Statement
The North Atlantic Oceanās multidecadal changes affect the atmosphere above it. Our study explores the energy processes behind this phenomenon. The North Atlantic Oceanās temperature distribution goes through a shift every 15ā20 years, persistently affecting the airās potential energy through the heat release related to vapor condensation. The changed potential energy converts into kinetic energy, causing the atmospheric circulation to alternate between different states. Our study provides a comprehensive explanation of how the ocean affects the regionās climate. This insight may contribute to making more accurate models and predictions of climate changes in the North Atlantic.
Abstract
The North Atlantic Ocean forcings are considered an important origin of the North Atlantic atmospheric multidecadal variability. Here, we reveal the energetics mechanisms of the phenomenon using the perturbation potential energy (PPE) theory. Supporting the previous model studies, a cyclic pattern involving the Atlantic multidecadal oscillation (AMO) and the North Atlantic tripole (NAT) is observed: positive AMO phase (AMO+) ā NATā ā AMOā ā NAT+, with a phase lag of approximately 15ā20 years. An atmospheric mode characterized by basinscale sea level pressure anomaly in the North Atlantic is associated with the AMO, which is termed the North Atlantic uniformity (NAU). The AMO+ induces positive uniform PPE anomalies over the ocean through precipitation heating, leading to decreased energy conversion to perturbation kinetic energy (PKE) and a large-scale anomalous cyclone. For the NAT+, tripolar precipitation anomalies result in tripolar PPE anomalies. Anomalous energy conversions occur where the PPE anomaly gradient is large, explained by an energy balance derived from thermal wind relationship. The PKE around 15Ā° and 50Ā°N (25Ā° and 75Ā°N) increases (decreases), forming the anomalous anticyclone and cyclone at subtropical and subpolar regions, respectively, known as the North Atlantic Oscillation (NAO). The reverse holds for the NATā and AMOā. As the phases of the ocean modes alternate, the energetics induce the NAUā, NAOā, NAU+, and NAO+ sequentially. In the multidecadal cycle, the accumulated energetics process is related to delayed effect, and the difference in variance explanation between the NAU and NAO is attributed to the feedback mechanisms.
Significance Statement
The North Atlantic Oceanās multidecadal changes affect the atmosphere above it. Our study explores the energy processes behind this phenomenon. The North Atlantic Oceanās temperature distribution goes through a shift every 15ā20 years, persistently affecting the airās potential energy through the heat release related to vapor condensation. The changed potential energy converts into kinetic energy, causing the atmospheric circulation to alternate between different states. Our study provides a comprehensive explanation of how the ocean affects the regionās climate. This insight may contribute to making more accurate models and predictions of climate changes in the North Atlantic.
Abstract
The export of the North Atlantic Deep Water (NADW) from the subpolar North Atlantic is known to affect the variability in the lower limb of the Atlantic meridional overturning circulation (AMOC). However, the respective impact from the transport in the upper (UNADW) and lower NADW (LNADW) layers, and from the various transport branches through the boundary and interior flows, on the subpolar overturning variability remains elusive. To address this, the spatiotemporal characteristics of the circulation of NADW throughout the eastern subpolar basins are examined, mainly based on the 2014-2020 observations from the transatlantic OSNAP (Overturning in the Subpolar North Atlantic Program) array. It reveals that the time-mean transport within the overturningās lower limb across the eastern subpolar gyre (ā13.0 Ā± 0.5 Sv) mostly occurs in the LNADW layer (ā9.4 Sv or 72% of the mean), while the lower limb variability is mainly concentrated in the UNADW layer (57% of the total variance). This analysis further demonstrates a dominant role in the lower limb variability by coherent intra-seasonal changes across the region that result from a basin-wide barotropic response to changing wind fields. By comparison, there is just a weak seasonal cycle in the flows along the western boundary of the basins, in response to the surface buoyancy-induced water mass transformation.
Abstract
The export of the North Atlantic Deep Water (NADW) from the subpolar North Atlantic is known to affect the variability in the lower limb of the Atlantic meridional overturning circulation (AMOC). However, the respective impact from the transport in the upper (UNADW) and lower NADW (LNADW) layers, and from the various transport branches through the boundary and interior flows, on the subpolar overturning variability remains elusive. To address this, the spatiotemporal characteristics of the circulation of NADW throughout the eastern subpolar basins are examined, mainly based on the 2014-2020 observations from the transatlantic OSNAP (Overturning in the Subpolar North Atlantic Program) array. It reveals that the time-mean transport within the overturningās lower limb across the eastern subpolar gyre (ā13.0 Ā± 0.5 Sv) mostly occurs in the LNADW layer (ā9.4 Sv or 72% of the mean), while the lower limb variability is mainly concentrated in the UNADW layer (57% of the total variance). This analysis further demonstrates a dominant role in the lower limb variability by coherent intra-seasonal changes across the region that result from a basin-wide barotropic response to changing wind fields. By comparison, there is just a weak seasonal cycle in the flows along the western boundary of the basins, in response to the surface buoyancy-induced water mass transformation.
Abstract
Extreme precipitation is expected to pose a more severe threat to human society in the future. This work assessed the historical performance and future changes in extreme precipitation and related atmospheric conditions in a large ensemble climate prediction dataset, the database for Policy Decision-making for Future climate change (d4PDF), over East Asia. Compared with the Tropical Rainfall Measuring Mission (TRMM) and fifth major global reanalysis produced by ECMWF (ERA5) datasets, the historical climate in d4PDF represents favorably the precipitation characteristics and the atmospheric conditions, although some differences are notable in the moisture, vertical motion, and cloud water fields. The future climate projection indicates that both the frequency and intensity of heavy precipitation events over East Asia increase compared with those in the present climate. However, when comparing the atmospheric conditions in the historical and future climates for the same precipitation intensity range, the future climate indicates smaller relative humidity, weaker ascent, less cloud water content, and smaller temperature lapse rate, which negatively affect generating extreme precipitation events. The comparison of the precipitation intensity at the same amount of precipitable water between the historical and future climates indicates that extreme precipitation is weaker in the future because of the more stabilized troposphere in the future. The general increase in extreme precipitation under future climate is primarily due to the enhanced increase in precipitable water in the higher temperature ranges, which counteracts the negative conditions of the stabilized troposphere.
Significance Statement
Extreme precipitation can have disastrous effects on human lives, economy, and ecosystems and is anticipated to significantly increase in both intensity and frequency under future climate. The purpose of this study is to investigate the mechanism for the future change of extreme precipitation. We examined the relationship between future changes in extreme precipitation and changes in the related atmospheric conditions. It is important for reducing uncertainties in future projections of extreme precipitation. Our results highlight that the future atmospheric condition is unfavorable for generating future extreme precipitation events in terms of stability and humidity changes. The increase in the column moisture content is the primary factor for the increase of extreme precipitation, which counteracts the negative conditions.
Abstract
Extreme precipitation is expected to pose a more severe threat to human society in the future. This work assessed the historical performance and future changes in extreme precipitation and related atmospheric conditions in a large ensemble climate prediction dataset, the database for Policy Decision-making for Future climate change (d4PDF), over East Asia. Compared with the Tropical Rainfall Measuring Mission (TRMM) and fifth major global reanalysis produced by ECMWF (ERA5) datasets, the historical climate in d4PDF represents favorably the precipitation characteristics and the atmospheric conditions, although some differences are notable in the moisture, vertical motion, and cloud water fields. The future climate projection indicates that both the frequency and intensity of heavy precipitation events over East Asia increase compared with those in the present climate. However, when comparing the atmospheric conditions in the historical and future climates for the same precipitation intensity range, the future climate indicates smaller relative humidity, weaker ascent, less cloud water content, and smaller temperature lapse rate, which negatively affect generating extreme precipitation events. The comparison of the precipitation intensity at the same amount of precipitable water between the historical and future climates indicates that extreme precipitation is weaker in the future because of the more stabilized troposphere in the future. The general increase in extreme precipitation under future climate is primarily due to the enhanced increase in precipitable water in the higher temperature ranges, which counteracts the negative conditions of the stabilized troposphere.
Significance Statement
Extreme precipitation can have disastrous effects on human lives, economy, and ecosystems and is anticipated to significantly increase in both intensity and frequency under future climate. The purpose of this study is to investigate the mechanism for the future change of extreme precipitation. We examined the relationship between future changes in extreme precipitation and changes in the related atmospheric conditions. It is important for reducing uncertainties in future projections of extreme precipitation. Our results highlight that the future atmospheric condition is unfavorable for generating future extreme precipitation events in terms of stability and humidity changes. The increase in the column moisture content is the primary factor for the increase of extreme precipitation, which counteracts the negative conditions.
Abstract
Coupled climate model simulations designed to isolate the effects of Arctic sea-ice loss often apply artificial heating, either directly to the ice or through modification of the surface albedo, to constrain sea ice in the absence of other forcings. Recent work has shown that this approach may lead to an overestimation of the climate response to sea-ice loss. In this study, we assess the spurious impacts of ice-constraining methods on the climate of an idealised aquaplanet general circulation model (GCM) with thermodynamic sea ice. The true effect of sea-ice loss in this model is isolated by inducing ice loss through reduction of the freezing point of water, which does not require additional energy input. We compare results from freezing point modification experiments with experiments where sea-ice loss is induced using traditional ice-constraining methods, and confirm the result of previous work that traditional methods induce spurious additional warming. Furthermore, additional warming leads to an overestimation of the circulation response to sea-ice loss, which involves a weakening of the zonal wind and storm track activity in midlatitudes. Our results suggest that coupled model simulations with constrained sea ice should be treated with caution, especially in boreal summer, where the true effect of sea-ice loss is weakest but we find the largest spurious response. Given that our results may be sensitive to the simplicity of the model we use, we suggest that devising methods to quantify the spurious effects of ice-constraining methods in more sophisticated models should be an urgent priority for future work.
Abstract
Coupled climate model simulations designed to isolate the effects of Arctic sea-ice loss often apply artificial heating, either directly to the ice or through modification of the surface albedo, to constrain sea ice in the absence of other forcings. Recent work has shown that this approach may lead to an overestimation of the climate response to sea-ice loss. In this study, we assess the spurious impacts of ice-constraining methods on the climate of an idealised aquaplanet general circulation model (GCM) with thermodynamic sea ice. The true effect of sea-ice loss in this model is isolated by inducing ice loss through reduction of the freezing point of water, which does not require additional energy input. We compare results from freezing point modification experiments with experiments where sea-ice loss is induced using traditional ice-constraining methods, and confirm the result of previous work that traditional methods induce spurious additional warming. Furthermore, additional warming leads to an overestimation of the circulation response to sea-ice loss, which involves a weakening of the zonal wind and storm track activity in midlatitudes. Our results suggest that coupled model simulations with constrained sea ice should be treated with caution, especially in boreal summer, where the true effect of sea-ice loss is weakest but we find the largest spurious response. Given that our results may be sensitive to the simplicity of the model we use, we suggest that devising methods to quantify the spurious effects of ice-constraining methods in more sophisticated models should be an urgent priority for future work.
Abstract
Recent simulations performed with the Community Earth System Model (CESM) have suggested a crucial role of sea-ice processes in AMOC hysteresis behaviour under varying surface freshwater forcing. Here, we further investigate this issue using additional CESM simulations and a novel conceptual ocean-sea-ice box model. The CESM simulations suggest that the presence of sea ice gives rise to the existence of statistical equilibria with a weak AMOC strength. This is confirmed in the conceptual model, which captures similar AMOC hysteresis behaviour as in the CESM simulation and where steady states are computed versus freshwater forcing parameters. In the conceptual model, transition probabilities between the different equilibrium states are determined using rare event techniques. The transition probabilities from a strong AMOC state to a weak AMOC state increase when considering sea-ice insulation effects and indicate that sea ice promotes these transitions. On the other hand, sea-ice insulation effects strongly reduce the probabilities of the reverse transition from a weak AMOC state to a strong AMOC state and this implies that sea ice also limits AMOC recovery. The results here indicate that sea-ice effects play a dominant role in AMOC hysteresis width and influence transition probabilities between the different equilibrium states.
Abstract
Recent simulations performed with the Community Earth System Model (CESM) have suggested a crucial role of sea-ice processes in AMOC hysteresis behaviour under varying surface freshwater forcing. Here, we further investigate this issue using additional CESM simulations and a novel conceptual ocean-sea-ice box model. The CESM simulations suggest that the presence of sea ice gives rise to the existence of statistical equilibria with a weak AMOC strength. This is confirmed in the conceptual model, which captures similar AMOC hysteresis behaviour as in the CESM simulation and where steady states are computed versus freshwater forcing parameters. In the conceptual model, transition probabilities between the different equilibrium states are determined using rare event techniques. The transition probabilities from a strong AMOC state to a weak AMOC state increase when considering sea-ice insulation effects and indicate that sea ice promotes these transitions. On the other hand, sea-ice insulation effects strongly reduce the probabilities of the reverse transition from a weak AMOC state to a strong AMOC state and this implies that sea ice also limits AMOC recovery. The results here indicate that sea-ice effects play a dominant role in AMOC hysteresis width and influence transition probabilities between the different equilibrium states.
Abstract
The importance of extreme event attribution rises as climate change causes severe damage to populations resulting from unprecedented events. In February 2019, a planetary wave shifted along the U.S.āCanadian border, simultaneously leading to troughing with anomalous cold events and ridging over Alaska and northern Canada with abnormal warm events. Also, a dry-stabilized anticyclonic circulation over low latitudes induced warm extreme events over Mexico and Florida. Most attribution studies compare the climate model simulations under natural or actual forcing conditions and assess probabilistically from a climatological point of view. However, in this study, we use multiple ensembles from an operational forecast model, promising statistical as well as dynamically constrained attribution assessment, often referred to as the storyline approach to extreme event attribution. In the globally averaged results, increasing CO2 concentrations lead to distinct warming signals at the surface, resulting mainly from diabatic heating. Our study finds that CO2-induced warming eventually affects the possibility of extreme events in North America, quantifying the impact of anthropogenic forcing over less than a weekās forecast simulation. Our study assesses the validity of the storyline approach conditional on the forecast lead times, which is hindered by rising noise in CO2 signals and the declining performance of the forecast model. The forecast-based storyline approach is valid for at least half of the land area within a 6-day lead time before the target extreme occurrence. Our attribution results highlight the importance of achieving net-zero emissions ahead of schedule to reduce the occurrence of severe heatwaves.
Abstract
The importance of extreme event attribution rises as climate change causes severe damage to populations resulting from unprecedented events. In February 2019, a planetary wave shifted along the U.S.āCanadian border, simultaneously leading to troughing with anomalous cold events and ridging over Alaska and northern Canada with abnormal warm events. Also, a dry-stabilized anticyclonic circulation over low latitudes induced warm extreme events over Mexico and Florida. Most attribution studies compare the climate model simulations under natural or actual forcing conditions and assess probabilistically from a climatological point of view. However, in this study, we use multiple ensembles from an operational forecast model, promising statistical as well as dynamically constrained attribution assessment, often referred to as the storyline approach to extreme event attribution. In the globally averaged results, increasing CO2 concentrations lead to distinct warming signals at the surface, resulting mainly from diabatic heating. Our study finds that CO2-induced warming eventually affects the possibility of extreme events in North America, quantifying the impact of anthropogenic forcing over less than a weekās forecast simulation. Our study assesses the validity of the storyline approach conditional on the forecast lead times, which is hindered by rising noise in CO2 signals and the declining performance of the forecast model. The forecast-based storyline approach is valid for at least half of the land area within a 6-day lead time before the target extreme occurrence. Our attribution results highlight the importance of achieving net-zero emissions ahead of schedule to reduce the occurrence of severe heatwaves.
Abstract
Precipitation in eastern China exhibits large interannual variability during July with the northward movement of the monsoon rain belt. Thus, eastern China usually experiences severe droughts and floods in July. However, the influences of underlying surface thermal drivers, particularly the land factors, remain poorly understood. This study investigates the leading modes of July precipitation in eastern China and their potential influencing factors. The first and second empirical orthogonal function (EOF) modes show meridional dipole and tripolar precipitation anomalies in eastern China, respectively. The EOF1 mode is found to be closely associated with sea surface temperature (SST) anomalies in the tropical Pacific and North Atlantic Oceans in June, while the EOF2 mode is mainly linked to anomalous Indian Ocean SST and Indochina Peninsula soil moisture in June. During years with a strong El NiƱoāSouth Oscillation (ENSO) signal, the EOF1 mode is mainly related to the enhanced Walker and Hadley circulations associated with the cold tropical Pacific SST anomalies. In contrast, during years with a weak ENSO signal, the Eurasian midlatitude wave train and the westward zonal overturning circulation associated with tripole-like North Atlantic SST anomalies play a leading role. The EOF2 mode is mainly influenced by Indian Ocean SST anomalies that alter the Walker circulation and by soil moisture anomalies in the Indochina Peninsula that induce an anomalous regional cyclonic circulation. Numerical experiments further demonstrated that the combined effects of soil moisture and SST exert a more substantial impact than their individual effects. These results emphasize the importance of surface thermal factors in understanding regional climate dynamics.
Abstract
Precipitation in eastern China exhibits large interannual variability during July with the northward movement of the monsoon rain belt. Thus, eastern China usually experiences severe droughts and floods in July. However, the influences of underlying surface thermal drivers, particularly the land factors, remain poorly understood. This study investigates the leading modes of July precipitation in eastern China and their potential influencing factors. The first and second empirical orthogonal function (EOF) modes show meridional dipole and tripolar precipitation anomalies in eastern China, respectively. The EOF1 mode is found to be closely associated with sea surface temperature (SST) anomalies in the tropical Pacific and North Atlantic Oceans in June, while the EOF2 mode is mainly linked to anomalous Indian Ocean SST and Indochina Peninsula soil moisture in June. During years with a strong El NiƱoāSouth Oscillation (ENSO) signal, the EOF1 mode is mainly related to the enhanced Walker and Hadley circulations associated with the cold tropical Pacific SST anomalies. In contrast, during years with a weak ENSO signal, the Eurasian midlatitude wave train and the westward zonal overturning circulation associated with tripole-like North Atlantic SST anomalies play a leading role. The EOF2 mode is mainly influenced by Indian Ocean SST anomalies that alter the Walker circulation and by soil moisture anomalies in the Indochina Peninsula that induce an anomalous regional cyclonic circulation. Numerical experiments further demonstrated that the combined effects of soil moisture and SST exert a more substantial impact than their individual effects. These results emphasize the importance of surface thermal factors in understanding regional climate dynamics.
Abstract
El NiƱo-Southern Oscillation (ENSO) is the dominant source of climate variability globally. Many of the most devastating impacts of ENSO are felt through extremes. Here we present and describe a spatially complete global synthesis of extreme temperature and precipitation relationships with ENSO. We also investigate how these relationships evolve under a future warming scenario under high greenhouse gas emissions using fourteen models from the Coupled Model Intercomparison Project Phase 6 (CMIP6) ensemble. Firstly, we demonstrate that models broadly capture observed ENSO teleconnections to means and extremes using the Twentieth Century Reanalysis version 3 (20CRv3). The models project that more regions will experience an amplification of the historical ENSO teleconnection with mean temperature and precipitation than a dampening under a high-emissions climate projection. The response of the ENSO teleconnection with extremes is very similar to the mean response, with even larger changes in some regions. Hence, regions that are predicted to experience an amplification of the ENSO teleconnection under future warming can also expect a comparable amplification in the intensity of extremes. Furthermore, models that suggest greater amplification of ENSO amplitude also tend to exhibit greater intensification of teleconnections. Future changes in regional climate variability may be better constrained if changes in ENSO itself are better understood.
Abstract
El NiƱo-Southern Oscillation (ENSO) is the dominant source of climate variability globally. Many of the most devastating impacts of ENSO are felt through extremes. Here we present and describe a spatially complete global synthesis of extreme temperature and precipitation relationships with ENSO. We also investigate how these relationships evolve under a future warming scenario under high greenhouse gas emissions using fourteen models from the Coupled Model Intercomparison Project Phase 6 (CMIP6) ensemble. Firstly, we demonstrate that models broadly capture observed ENSO teleconnections to means and extremes using the Twentieth Century Reanalysis version 3 (20CRv3). The models project that more regions will experience an amplification of the historical ENSO teleconnection with mean temperature and precipitation than a dampening under a high-emissions climate projection. The response of the ENSO teleconnection with extremes is very similar to the mean response, with even larger changes in some regions. Hence, regions that are predicted to experience an amplification of the ENSO teleconnection under future warming can also expect a comparable amplification in the intensity of extremes. Furthermore, models that suggest greater amplification of ENSO amplitude also tend to exhibit greater intensification of teleconnections. Future changes in regional climate variability may be better constrained if changes in ENSO itself are better understood.
