Search Results

You are looking at 111 - 120 of 46,329 items for :

  • Refine by Access: All Content x
Clear All
Pin-Fang Lin, Pao-Liang Chang, Ben Jong-Dao Jou, James W. Wilson, and Rita D. Roberts

1. Introduction The purpose of this study is to investigate the characteristics of afternoon thunderstorms on the island of Taiwan during the warm season (May–October 2005–2008) for days when synoptic forcing was weak. It is particularly challenging to forecast thunderstorms in Taiwan, which is a mountainous island characterized by the Central Mountain Range (CMR) running across most of it in a north-northeast–south-southwest orientation at an average height of about 2 km ( Fig. 1 ). Mountains

Full access
A. R. Atwood, E. Wu, D. M. W. Frierson, D. S. Battisti, and J. P. Sachs

spatial and temporal heterogeneity of the LIA cooling signal is likely the result of a complex array of forcings, feedbacks, and internal variability operating in the climate system ( Kaufman et al. 2009 ; Fernandez-Donado et al. 2013 ; Lehner et al. 2013 ). A number of different forcing mechanisms (including solar, volcanic, land use, greenhouse gas, and orbital forcings) acting in concert with atmosphere, ocean, and sea ice feedbacks have been invoked to explain the cold conditions during the LIA

Full access
Erik J. L. Larson and Robert W. Portmann

1. Introduction Accurate radiative forcing estimates are necessary to understand the global energy budget and future climate responses to anthropogenic and natural emissions. Estimating the radiative forcing that is driving climate change is difficult because of the complex climate response to the many individual forcing agents. It is currently impossible to directly measure the globally averaged radiative forcing. Observations from space measure the top-of-atmosphere (TOA) radiative imbalance

Full access
Yi Deng, Tae-Won Park, and Ming Cai

evaluating climate feedbacks ( Lu and Cai 2009 ; Cai and Lu 2009 ). Here, for the first time, we adopt CFRAM to understand the most important mode of subseasonal variability in the northern extratropics. The main objective is to obtain a quantitative assessment of the relative importance of radiative and dynamical forcing in generating NAM-related temperature anomalies and identify (if any) differences between atmospheric and surface responses and among different geographical locations. Section 2 of

Full access
Shao-Yi Lee, Ho-Jeong Shin, and Chien Wang

1. Introduction Field observations in recent decades have revealed an abundance of anthropogenic aerosols, particularly absorbing aerosols, over South Asia and its surrounding ocean during the dry season ( Ramanathan et al. 2001 ). Modeling studies and observation-based analyses have indicated that the radiative effects of these aerosols can interrupt not just localized meteorological features but also large-scale climate features such as monsoons. Using prescribed direct radiative forcing

Full access
Fukai Liu, Jian Lu, Oluwayemi A. Garuba, Yi Huang, L. Ruby Leung, Bryce E. Harrop, and Yiyong Luo

1. Introduction The ocean is an important regulator of the global climate. Owing to its large heat capacity and circulation, the ocean has large influences on both the mean state and variability of the climate, as well as the climate response to external forcings. Unlike the atmosphere, which has a short memory, with long time scales the ocean is the pacemaker for the slow evolution of regional (e.g., Read and Gould 1992 ; Delworth et al. 1993 ; Chang et al. 2008 ) and global climate (e

Full access
Benjamin G. M. Webber, David P. Stevens, Adrian J. Matthews, and Karen J. Heywood

; McPhaden 1999 ) and the Madden–Julian oscillation (MJO) ( Han et al. 2001 ; Webber et al. 2010 ). Equatorial Kelvin waves exhibit a single equatorial SSH maximum, while equatorial Rossby waves have more complex meridional structures, the simplest and most commonly observed being the first meridional mode with symmetric off-equatorial SSH maxima ( Chelton et al. 2003 ). A westerly wind burst on the equator will generate Ekman convergence, thus forcing a positive SSH anomaly on the equator, along with

Full access
Aimée B. A. Slangen, John A. Church, Xuebin Zhang, and Didier P. Monselesan

Bouttes and Gregory (2014) used a single climate model (FAMOUS) driven by surface fluxes from a range of CMIP3 and CMIP5 models to study regional patterns in sea level under a 1% per year increase in CO 2 concentration scenario to determine the main drivers of change. Recently, Bilbao et al. (2015) identified a scenario-independent sea level pattern in response to increasing anthropogenic forcings in sea level projections for the twenty-first century, valid for all representative concentration

Full access
Olivier Arzel, Alain Colin de Verdière, and Matthew H. England

proposed so far. Jumps between cold stadials and warm interstadials were first reproduced in noise-free models with the help of a periodic surface freshwater forcing ( Ganopolski and Rahmstorf 2001 ). The origin of the imposed 1500-yr periodicity was left unspecified, but it was speculated that it might be related to solar forcing, as suggested by van Geel et al. (1999) and Bond et al. (2001) . Stochastic resonance, a process that results from a combination of a weak (subthreshold) periodic forcing

Full access
Gualtiero Badin and Richard G. Williams

1. Introduction The overturning circulation is a consequence of contrasts in surface buoyancy forcing, involving an air–sea exchange between surface waters and the overlying atmosphere. Walin (1982) provided a clear theoretical framework setting out how air–sea heat fluxes and interior mixing lead to an area-integrated transformation of warm to cold water across a temperature layer. Despite the local uncertainty in air–sea fluxes, Speer and Tziperman (1992) extended this framework to

Full access