Seismology and Climatology: A Study of Seismological Impacts of Climate Change in Indonesia

Climate change has been a matter of discourse for the last several decades. Much research has been conducted regarding the causes and impacts of climate change around the world. The current research contributes to the knowledge of the influence of climate change on our environment, with emphasis on earthquake occurrences in the region of Indonesia. Using global temperature anomaly as a measure of climate change, and earthquake data in Indonesia for the period 1900-2022, the paper seeks to find a relationship (if any) between the two variables. Statistical methods used include normal distribution analysis, linear regression and correlation test. The results show peculiar patterns in the progression of earthquake occurrences as well as global temperature anomaly occurring in the same time periods. The findings also indicated that the magnitudes of earthquakes remained unaffected by global temperature anomalies over the years. Nonetheless, there appears to be a potential correlation between temperature anomalies and the frequency of earthquake occurrences. As per the results, an increase in temperature anomaly is associated with a higher frequency of earthquakes.

Climatology

Climatology is the study of the“climate”-the weather over a long time.The climate doesn’t always stay the same.It changes slowly over hundreds or even thousands of years.For example,we know that in the past large parts of the world had lots of ice and snow.This slow change is a normal part of our world,but today’s climate is changing very quickly.

A Review on Clustering Methods for Climatology Analysis and Its Application over South America

South America’s climatic diversity is a product of its vast geographical expanse, encompassing tropical to subtropical latitudes. The variations in precipitation and temperature across the region stem from the influence of distinct atmospheric systems. While some studies have characterized the prevailing systems over South America, they often lacked the utilization of statistical techniques for homogenization. On the other hand, other research has employed multivariate statistical methods to identify homogeneous regions regarding temperature and precipitation, but their focus has been limited to specific areas, such as the south, southeast, and northeast. Surprisingly, there is a lack of work that compares various multivariate statistical techniques to determine homogeneous regions across the entirety of South America concerning temperature and precipitation. This paper aims to address this gap by comparing three such techniques: Cluster Analysis (K-means and Ward) and Self Organizing Maps, using data from different sources for temperature (ERA5, ERA5-Land, and CRU) and precipitation (ERA5, ERA5-Land, and CPC). Spatial patterns and time series were generated for each region over the period 1981-2010. The results from this analysis of spatially homogeneous regions concerning temperature and precipitation have the potential to significantly benefit climate analysis and forecasts. Moreover, they can offer valuable insights for various climatological studies, guiding decision-making processes in diverse fields that rely on climate information, such as agriculture, disaster management, and water resources planning.

2022年广东省气候特征及其影响

2022年全省年平均气温22.2℃,与常年基本持平,但各月气温起伏波动大;高温日数31.8 d,为历史第2多,其中7月出现历史第2强高温过程。年平均降水量2 057.6 mm,较常年偏多14%,但阶段性明显。3月24日开汛,较常年偏早18 d,前汛期出现了近20年最强5月暴雨过程以及有气象记录以来第3强“龙舟水”,北江发生超百年一遇洪水。初台偏晚,全年共有5个台风登陆和1个台风严重影响,登陆个数较历史平均偏多1.3个。2月出现历史同期少见的持续低温阴雨寡照天气。9—10月温高雨少,气象干旱严重。灰霾日数继续维持较低水平。2022年广东省气象灾害严重,气候影响综合评价为较差年景。

广东省2024年4月气候概况及极端性分析

2024年4月,广东省平均气温创历史4月新高,4月降水为有气象记录以来最多,但空间分布不均,呈北多南少。月内出现2次冷空气过程,同时先后出现了1981年以来最强的3轮4月份强降水过程,具有强对流明显、暴雨区重叠、累积雨量大、极端性显著的特点。

新气候态下广东省高温特征及影响

基于1951-2021年广东省86个国家站的逐日高温资料,采用常规时序、空间统计等方法对新气候态下广东省高温的时空特征进行分析,结果表明:广东省年高温日数1951-2021年呈显著增加趋势,尤其进入21世纪以来高温日数增加趋势明显;高温天气主要发生在6-9月,集中在7-8月,其中也包括各地极端最高气温。广东省年平均高温日数呈南低、北高的空间分布,并存在3个高值中心;极端最高气温从西北向沿海递减。高温天气对生产生活将产生诸多不利影响,如气象敏感性疾病高发,火灾风险加大,农作物产量、质量降低,能源供应压力和用电负荷增加,道路交通事故频发等。

基于高分辨格点数据东北水稻延迟型冷害风险评估及保险费率厘定

利用5km×5km空间分辨率3h时间分辨率的气象格点数据集,研究东北地区水稻延迟型冷害风险及其保险费率的厘定。基于东北地区1981-2010年5-9月平均温度的格点数据集和99个气象站的站点观测数据,以相关系数和均方根误差评价格点气象数据在东北地区的可用性。以日平均气温稳定通过10℃和18℃的日数作为获取水稻气候安全种植区域的指标,在水稻气候安全种植范围内,分析东北地区水稻延迟型冷害的空间分布特征,确定保险费率。结果表明,东北地区1981-2010年5-9月平均温度气象站点观测数据与格点数据的相关系数高,均方根误差小,表明格点数据在东北地区可用。水稻气候安全种植区域占东北的56.5%,主要分布在辽宁省、吉林省中西部、黑龙江省西南部和东北部、蒙东西部及东部与辽宁和吉林省接壤的区域。在水稻气候安全种植区内,水稻延迟型冷害发生频率呈南低北高,中间低东西高的分布特征,且重度延迟型冷害发生频率最高。低温冷害风险指数空间分布与之相似,内蒙古西部和东北部、黑龙江北部和吉林西部局部地区是风险指数的高值区。东北地区1981-2010年水稻延迟型冷害的天气指数保险费率在空间分布上与东北地区低温冷害风险指数的空间分布相似,呈南部低,北部高,中间低,东西高的特征,整个区域的保险费率在0.010~0.094,可为保险公司制定具体费率提供参考。

2022年5月广东气温异常偏低的气候特征及其成因

基于NCEP/NCAR再分析数据集、NOAA海温和向外长波辐射以及国家气象观测站平均气温数据,采用线性趋势、合成分析方法,探讨2022年5月广东气温异常偏低的气候特征及其成因。结果表明,2022年5月平均气温较常年低1.9℃,创下广东1961年以来最低值;该次异常低温是在拉尼娜事件背景下发生的,通过大气环流对欧亚大陆气候产生显著性影响;欧亚中高纬环流经向度偏大,东亚大槽与蒙古高压偏强,引导东西伯利亚及其以北地区过多的冷空气向南侵袭,同时低纬活跃的偏南暖湿气流与北方冷空气在广东上空交汇致雨成云,地表非绝热加热与大气下沉增温效应受抑制,进而导致了2022年5月的气温异常偏低。

Classifying moisture sources associated with snowfall in the mountains of Lesotho

An average of eight snowfall events occur each year in the eastern Lesotho Highlands.These snowfall events are typically associated with cut-off low(CoLs)systems and mid-latitude cyclones.However,the moisture sources of the snowfall are unclassified and unclear.The Hybrid Single-Particle Lagrangian Integrated Trajectory(HYSPLIT)model,an air mass back trajectory model,has been used to evaluate moisture source waters locally in southern Africa and internationally in China and Europe.This study uses HYSPLIT to determine the source moisture of snow in Lesotho.A list of all 82 snowfall events in Lesotho spanning 2017 to 2022 was compiled using the Snow Report SA Instagram page,including the date and location of snowfall.A 72-hour back trajectory for each snowfall event was initiated for both Afriski and the whole of Lesotho.This amounts to models of moisture source trajectories for 28 and 82 snowfall days,respectively.These air mass pathways are classified according to their frequency per snowfall event,per month in the snow season,per year and for the full period.From this,associated moisture source regions and dominant air mass trajectories were identified.This study reports that the air mass trajectories associated with Afriski and Lesotho as a whole are very similar.The most common pathway of air mass trajectories transporting snow-bearing moisture to Lesotho was an inland trajectory from the northern regions of southern Africa.This pathway makes up 16.6%of all trajectories reported and is associated with the Angola Low,the Congo Air Boundary and the St.Helena High Pressure.

Comprehensive applicability evaluation of four precipitation products at multiple spatiotemporal scales in Northwest China

Precipitation plays a crucial role in the water cycle of Northwest China.Obtaining accurate precipitation data is crucial for regional water resource management,hydrological forecasting,flood control and drought relief.Currently,the applicability of multi-source precipitation products for long time series in Northwest China has not been thoroughly evaluated.In this study,precipitation data from 183 meteorological stations in Northwest China from 1979 to 2020 were selected to assess the regional applicability of four precipitation products(the fifth generation of European Centre for Medium-Range Weather Forecasts(ECMWF)atmospheric reanalysis of the global climate(ERA5),Global Precipitation Climatology Centre(GPCC),Climatic Research Unit gridded Time Series Version 4.07(CRU TS v4.07,hereafter CRU),and Tropical Rainfall Measuring Mission(TRMM))based on the following statistical indicators:correlation coefficient,root mean square error(RMSE),relative bias(RB),mean absolute error(MAE),probability of detection(POD),false alarm ratio(FAR),and equitable threat score(ETS).The results showed that precipitation in Northwest China was generally high in the east and low in the west,and exhibited an increasing trend from 1979 to 2020.Compared with the station observations,ERA5 showed a larger spatial distribution difference than the other products.The overall overestimation of multi-year average precipitation was approximately 200.00 mm and the degree of overestimation increased with increasing precipitation intensity.The multi-year average precipitation of GPCC and CRU was relatively close to that of station observations.The trend of annual precipitation of TRMM was overestimated in high-altitude regions and the eastern part of Lanzhou with more precipitation.At the monthly scale,GPCC performed well but underestimated precipitation in the Tarim Basin(RB=-4.11%),while ERA5 and TRMM exhibited poor accuracy in high-altitude regions.ERA5 had a large bias(RB≥120.00%)in winter months and a strong dispersion(RMSE≥35.00 mm)in summer months.TRMM showed a relatively low correlation with station observations in winter months(correlation coefficients≤0.70).The capture performance analysis showed that ERA5,GPCC,and TRMM had lower POD and ETS values and higher FAR values in Northwest China as the precipitation intensity increased.ERA5 showed a high capture performance for small precipitation events and a slower decreasing trend of POD as the precipitation intensity increased.GPCC had the lowest FAR values.TRMM was statistically ineffective for predicting the occurrence of daily precipitation events.The findings provide a reference for data users to select appropriate datasets in Northwest China and for data developers to develop new precipitation products in the future.

海气相互作用在模式FGOALS-g3模拟东亚夏季风及其对前冬El Niño响应中的贡献

本文基于观测、再分析资料和中国科学院大气物理研究所大气科学和地球流体力学数值模拟国家重点实验室(LASG)最新版本气候系统模式FGOALS-g3,探究了海气相互作用在模拟东亚夏季风及其对前冬El Niño响应中的贡献。大气环流模式(AGCM)模拟的气候态夏季风雨带偏东,东亚季风区表现为干偏差,耦合模式(CGCM)虽模拟出了夏季风雨带的位置,但降水仍偏弱。AGCM由于缺乏海气耦合过程,夏季西北太平洋地区对流模拟过强,使得副热带高压(简称副高)偏东、南中国海季风槽偏东,造成东亚夏季风雨带偏东;东亚陆地区域水汽偏少,也是降水干偏差的一个重要原因,此两项可以解释70%以上的干偏差。在考虑海气相互作用后,西北太平洋的降水正异常减弱了局地海表温度,因此CGCM显著改进了副高以及南中国海季风槽偏东等偏差,使得夏季风雨带位置得到改进,季风区降水干偏差减小了36%,但由于水汽偏少,水汽纬向输送偏少,东亚季风区仍维持着显著的干偏差。另一方面,对前冬El Niño的响应,CGCM能够再现El Niño衰减年夏季印度—西太平洋电容器效应(IPOC机制)对西北太平洋异常反气旋(WNPAC)的维持作用及偶极型分布的降水异常。而AGCM中夏季西北太平洋以及孟加拉湾、印度半岛周围海域对流对于海温的响应过于敏感,一方面西北太平洋局地暖异常造成的对流质量输送一定程度上抑制了WNPAC的建立,另一方面孟加拉湾、印度半岛周围海域过强的上升异常,通过局地环流,抑制了其南侧印度洋的对流异常,导致无法模拟出IPOC机制对衰减年夏季WNPAC的维持作用。因此,缺乏海气耦合过程是AGCM不能模拟出东亚夏季风对前冬El Niño滞后响应的关键原因。

近10年深圳市短时强降水及风险统计分析

利用深圳市近10年全市自动气象站逐时降水量资料,分析深圳市短时强降水气候特征、风险指数、影响系统,结果表明:(1)深圳市短时强降水日数呈现逐年增长的趋势,2009年至今一直处于高位波动中。短时强降水日数月变化呈现倒U型分布,6—8月是防范短时强降水风险的关键时期,中午至傍晚是短时强降水的易发时段。(2)建立了短时强降水风险指数,结果表明该指数可以指示各区的高风险地区。(3)深圳市短时强降水的天气系统分为5种类型:热带气旋和热带扰动外围环流影响、切变线和冷空气影响、季风低压、西南风急流辐合、副高边缘东风波动。

中国汛期雨带的客观划分及其相关环流特征

本文利用1961—2016年中国汛期逐候降水的旋转经验正交函数分解(Rotated Empirical Orthogonal Function,REOF)方法对中国汛期雨带进行客观划分。根据REOF模态空间分布以及主成分的气候态平均确定了中国汛期6个主要雨带的落区和时间,并揭示了各雨带气候态环流特征。江南春雨雨带主要发生在长江以南地区,对应时间为26—27候;南方雨季的雨带落区主要在两广至福建地区,对应时间为33—34候;江南及中下游梅雨主要落区在长江以南和长江中下游流域,对应时间分别为34—35和36—37候;华北东北雨季落区在华北至东北地区,发生时间为41—42候;华西秋雨落区在秦岭及其周围地区,对应发生时间为49—52候。在雨带划分的基础上,进一步揭示了各个雨带典型的对流层中高低气候态环流特征。可为客观定义汛期雨带及各雨带气候预测提供参考。

基于不同再分析资料南海夏季风爆发的气候特征和年际变率

南海夏季风爆发标志着东亚夏季风的全面建立,其对我国主汛期雨带分布具有重要指示意义。本文对比了日本气象厅JRA-55、欧洲中期数值预报中心ERA5、中国气象局CRA-40和美国国家环境预测中心NCEP1四套再分析资料中南海夏季风爆发的气候特征和年际变率。结果表明,在四套再分析资料中,南海夏季风爆发期间大气环流和降水场突变的气候特征基本一致,但CRA-40资料的高空暖中心和降水均明显强于JRA-55、ERA5和NCEP1资料。同时,本文分别采用850 hPa纬向西风(U850)盛行、对流层中上部平均经向温度梯度(MTG)反转和南海地区对流建立来定义南海夏季风爆发时间。基于不同的定义指标,四套再分析资料所确定的南海夏季风爆发时间在大多数年份一致,表现为高、低空环流的调整伴随着南海季风对流的建立,环流和降水场完全耦合,且U850定义指标对资料的敏感度高于MTG定义指标。但在个别年份,三种指标所确定的南海夏季风爆发时间差异明显,这时高、低空环流和降水场的耦合关系不明确。当U850、MTG和OLR所定义南海夏季风爆发时间的年际变率一致时,4~5月海温异常场呈现典型的ENSO型分布特征,说明这些年份南海夏季风爆发可能受热带海—气相互作用影响,其中5月孟加拉湾的海温异常可能是ENSO影响南海夏季风爆发时间的关键。而当三种定义方式所得南海夏季风爆发时间的年际变率不一致时,最明显的海温异常信号出现在北太平洋加州沿岸,说明中纬度海—气相互作用对南海夏季风爆发时间也存在潜在调制作用。

近50年鉴江流域日照时数的气候特征

利用线性趋势、M-K突变分析等方法详细分析了1973—2022年鉴江流域年、季日照时数气候特征,结果表明:近50年来,鉴江流域春季日照时数呈不显著的上升趋势,年及其他3季则呈不显著下降趋势。从9年滑动平均日照时数看,夏、秋季主要集中在550~640 h之间,春、冬季主要集中在300~400 h之间。春季日照时数在2007年前后发生突变,秋季在1995年前后发生突变。年日照时数主要存在2~6年显著周期。空间分布上,年日照时数呈现由南向中北部递减分布。相对湿度、降水量、降水日数、总云量以及低云量与日照时数显著负相关,夏季平均气温和平均最高气温与日照时数呈显著正相关。

梅州短时强降水时空分布特征及地形影响

利用2010-2020年梅州市113个自动气象站的逐小时降水资料,运用统计学和空间插值方法,对梅州市短时强降水时空分布特征及地形影响进行分析。结果表明:短时强降水年均频次整体无明显增多或者减少趋势,存在3年左右短周期波动,空间分布为南北大中间小。短时强降水主要发生在4-9月,呈5、8月双峰分布;前汛期主要分布在平远蕉岭、后汛期分布在丰顺,分别主要由西南季风和热带天气系统影响。短时强降水高发时段为下午到傍晚,但极端雨强出现时间比高发时段推迟2 h左右;前汛期北部存在一定的夜雨特征。梅州短时强降水高发区主要分布于迎风坡喇叭口地形处,低值区分布于山脉背风坡的平原低地、盆地处。

复合型人才培养理念下的高师地理专业教学探究——以“气象学与气候学”为例

面对新形势下社会对于多样化人才的需求,高师地理专业的人才培养模式也从单一型转向复合型。“气象学与气候学”作为高师地理科学专业一门重要的基础课,有着广阔的就业市场与社会需求,是培养复合型地理人才必不可少的一环。基于复合型人才培养理念对“气象学与气候学”课程进行教学改革,包括优化授课方式、优化理论教学环节、优化实验教学环节三个方面,通过多管齐下的方式训练学生的理科思维,激发学生的创造力与科研兴趣,培养学生的动手能力,从而服务于复合型地理人才的培养目标。

广东降水的日变化特征

基于2008-2020年广东86个国家站逐时降水数据,分析了广东降水的日变化特征。结果表明:广东大部分站点降水量、降水频率和降水强度日峰值出现在午后至傍晚,仅韶关、清远和沿海地区等一些站点清晨出现日峰值;降水量日变化幅度较降水强度略大,降水频率日变幅较小。各个区域降水频率的日变化均表现为双峰型,其中粤西北和粤东南清晨降水频率更大,粤西南清晨和午后相当,粤中和粤东北午后更大;各区域降水强度的日变化表现为峰值出现在午后的单峰型;降水量的日峰值主要出现在午后。不同季节降水日峰值出现时间不同,降水双峰型的日变化特征主要是由于不同季节降水日峰值出现时间不同造成的。另外,不同区域降水的日变化表现出随季节变化提前或推后的特征。

岳普湖县无花果气候品质认证指标及评价分析

利用1991—2022年岳普湖国家一般气象站的逐日平均气温、极端最高气温、极端最低气温、降水量、日照时数等地面观测数据,采用气候倾向率和累积距平气候统计方法,提出喀什地区岳普湖县无花果气候品质认证的方法,初步分析总结气象条件对其物候期的影响和气象因素、灾害气象条件对其品质的影响。2022年样点果园中喀什地区岳普湖县岳普湖乡无花果园无花果气候品质评价结果为特优。研究结论可为岳普湖无花果实品质的提高和未来合理化区域管理提供依据。

韶关汛期不同持续时间的降水特征分析

基于2008—2021年韶关8个国家站的逐时降水数据,分析了韶关汛期不同持续时间降水的特征,结果表明:韶关汛期降水的平均持续时间为3.9 h,持续2~6 h降水事件的累计降水量较大,随着持续时间的增长,累计降水量逐渐减少,降水频次迅速减小,持续时间大于10 h降水事件的降水强度较大。短时降水事件主要始发于午后到傍晚,降水量峰值出现在14:00—20:00;持续性降水事件主要始发于夜间到清晨,降水量的峰值出现在清晨;不同持续时间的降水事件均较少始发于08:00—12:00,且该时段降水量较少。短时降水午后到傍晚的降水量峰值是降水频次和降水强度共同作用下形成,清晨的次峰值主要取决于降水频次;持续性降水的降水频次在各个时次相差不大,其降水量日变化主要来自于降水强度的贡献。前汛期(4—6月)持续性降水和短时降水各占一定的比例,持续性降水略多;后汛期(7—9月)以短时降水为主。