Rate Of Precipitation Increase Research Articles

Factors Contributing to Historical and Future Trends in Arctic Precipitation

AbstractThe Arctic is notable as a region where the greatest rate of increase in precipitation associated with global warming is anticipated. The Arctic precipitation simulated by the Coupled Model Intercomparison Project Phase 6 models showed a strong increasing trend since the 1980s. We found that the forcing factor of the trend is a combination of the continued strengthening of greenhouse gas forcing and the leveling off of aerosol forcing dominated in earlier periods. From an energetic perspective, we found that the increased atmospheric radiative cooling and reduced sensible heat transport from lower latitudes contributed equally to the recent increase in Arctic precipitation. The combination of these two energetic factors suggests a doubling of the Arctic amplification factor for precipitation relative to that for temperature. Future Arctic precipitation will change in proportion to the temperature change, and the fractional contributions of the energetic factors will remain stable across various scenarios.

Effects of Ecological Restoration and Climate Change on Herbaceous and Arboreal Phenology.

With global climate change, changes in vegetation phenology have become increasingly evident. Horqin Sandy Land is located near the eastern part of the West Liaohe River. It is the largest sandy land in China and its ecological environment is fragile. Investigating the changes in vegetation phenology in these sandy areas and determining the relationship between vegetation phenology and meteorological factors are of great importance for predicting the impacts of future climate change and understanding the response mechanisms of ecosystems. In this study, we used the time series of the Normalized Difference Vegetation Index (NDVI) from 2000 to 2021 and extracted the vegetation phenology in the Horqin Sandy Land using high-order curve fitting methods, including the start date of the growing season (SOS), the end date of the growing season (EOS), and the length of the growing season (LOS). We analyzed their temporal variation and used partial correlation analysis to determine their relationship with meteorological factors (temperature and precipitation). In addition, we compared the phenology and microclimate of forest and grassland within the study area. In the Horqin Sandy Land, the vegetation SOS was concentrated between the 115th and 150th day, the EOS was concentrated between the 260th and 305th day, and the LOS ranged from 125 to 190 days. Over the past 22 years, the SOS, EOS, and LOS of vegetation in the Horqin Sandy Land showed trends of delay, shift, and extension, with rates of change of 0.82 d/10a, 5.82 d/10a, and 5.00 d/10a, respectively. The start date of the growing season in the Horqin Sandy Land was mainly influenced by precipitation in April of the current year, while the end date was mainly influenced by precipitation in August of the current year. Overall, the SOS in the forested areas of the Horqin Sandy Land was slightly later than in the grasslands, but the EOS in the forested areas was significantly later than in the grasslands, resulting in a longer LOS in the forests. In addition, annual precipitation and the rate of precipitation increase were higher in the forested areas than in the grasslands, but soil temperature was higher in the grasslands than in the forests. Vegetation phenology in the Horqin Sandy Land has undergone significant changes, mainly manifested in the delayed end date of the growing season, the extended length of the growing season, and the differences between forest and grassland. This indicates that climate change has indeed affected phenological changes and provides a theoretical basis for subsequent ecological restoration and desertification prevention efforts in the region.

Historical Trends Associated with Annual Temperature and Precipitation in Aegean Turkey, Where Are We Heading?

The trend analysis of annual temperature (daily average) and total precipitation has been conducted for 14 stations located in the Aegean Region, Turkey. The Sen, Spearman’s rho, and Mann-Kendall test methods are used in the detection of the historical trends in the region. The Pettitt test is also implemented to find the significance of the trend, while the Theil-Sen approach is applied to detect the change point(s) in the time series. Findings of the following study indicate that both precipitation and temperature time series in the selected stations depict statistically significant trends with increasing nature. The rate of increase in precipitation and temperature by the Theil-Sen test is found to be 4.2–7.9 mm/year and 0.20–0.35 °C/decade, respectively. It is also found that the turn points of the temperature trends determined by the Pettitt test occurred in 1998 for all the stations. According to the results, the magnitude of the extreme events would change in the future, which may help in conceptualizing the framework and the resilience of the infrastructures against climate change.

Increasing annual and extreme precipitation in permafrost-dominated Siberia during 1959–2018

Increased attention to precipitation changes in permafrost-dominated Siberia is promoted by intensified flooding under climate warming. The observed daily precipitation spanning 60 years (1959–2018) from 129 meteorological stations across the Siberian lowlands with elevations less than 500 m (50°N–70°N, 60°E–140°E) captures significant changes in both annual and extreme precipitation. For 1959–2018, the average annual precipitation over the Siberian lowlands was 428 ± 110 mm. The average annual precipitation in non-permafrost zones was approximately 458 ± 114 mm, larger than that in permafrost zones (407 ± 102 mm). Additionally, non-permafrost zones experienced greater intensities and frequencies of precipitation extremes than permafrost zones according to four extreme precipitation indices (i.e., R99p, R95p, R×5d, and R10mm). However, the rate of increase in precipitation and precipitation extremes was greater in permafrost zones than in non-permafrost zones. These results obtained from in situ observations are generally consistent with ERA5 precipitation reanalysis data. Given faster warming in permafrost than in non-permafrost zones, the rate of increase in precipitation and precipitation extremes in permafrost zones also respond more than those in non-permafrost zones. In particular, summer precipitation in permafrost zones accelerates permafrost degradation, and the release of carbon dioxide and methane from permafrost sediments is very likely to have positive feedback effects on regional temperature and precipitation increases. Our results indicate that Siberia will face risks attributable to increased precipitation and precipitation extremes in the context of climate warming, and such risks will be greater in the permafrost zones than in the non-permafrost zones.

Projections of precipitation over China based on CMIP6 models

Precipitation fluctuations are continuously threatening the environment and may cause huge economic losses. In present study, the precipitation over China has been evaluated under five principal shared socioeconomic pathways (SSPs) scenarios during 2015–2099 based on eight CMIP6 models bias-corrected by the method of Equidistant Cumulative Distribution Functions. The results showed that (1) the simulated precipitation in China was in good agreement with observed precipitation for the eight CMIP6 models during 1961–2014, especially for the UKESM1-0-LL and MIROC6. However, the simulated annual mean precipitation has been significantly overvalued in the Southwest River basin (> 50%), while it was undervalued in the higher elevations of the Northwest River basin (< − 60%); (2) the annual mean precipitation will show a fluctuating upward trend during 2015–2099 over China under all the SSPs scenarios for the eight CMIP6 models. The rate of precipitation increase over north China will be higher than that in south China, especially in the Northwest River basin (reach 57.44% in the 2090s under the SSP5-8.5 for the ensemble mean). This increase of the precipitation in north China might alleviate the shortage of water there, but will not change the pattern of more rain in the south and less in the north; (3) in the southeastern basins, the precipitation of the multi-model ensemble (MME) and MIROC6 during 2011–2020 will be lower than that of 1961–2010 (− 6.53 to − 0.06%) under all SSPs scenarios. While the precipitation will increase obviously under all the SSPs scenarios, especially for the SSP5-8.5 scenario after the year of 2060; (4) the bias of the MME was much lower than that of individual CMIP6 models, and the bias of lower SSPs scenarios will be relatively lower. Generally, uncertainty ranges of precipitation fluctuations in north China (15.31–79.26%) will be higher than those in south China (16.06–7.55%). These findings revealed the projections and uncertainties of CMIP6 precipitation over China, which will be helpful for a better understanding of the future evolution of precipitation in China at large scale and in other regions of the world.

Clausius-Clapeyron Scaling of Extremely Heavy Precipitations: Case Studies of the July 2017 and July 2018 Heavy Rainfall Events over Japan

The usefulness of Clausius–Clapeyron (CC) scaling in explaining extremely heavy precipitations is explored in the present-day climate and in pseudo-global-warming (PGW) conditions. This is analyzed by conducting regional-scale numerical simulations at 1-km grid resolution for two recent extreme rainfall events that occurred in Japan: the case in northern Kyushu during 5–6 July 2017 and the case in Shikoku Island during 5–8 July 2018. The Weather Research and Forecasting (WRF) model was used for the simulation, and the data samples were collected at each grid point individually for each hour over the two regions. We found that the frequency and intensity of extremely heavy precipitation associated with the two events are increased under PGW conditions. The extremely heavy precipitations (> 50 mm h−1) followed CC scaling for the temperatures up to 22°C in the present-day climate, while those under the PGW conditions followed CC-scaling up to 24°C. The peak intensity of the extremely heavy precipitations in the precipitation-temperature relationship is found as ∼ 140 mm h−1 at 25°C in the present-day climate, while the same with PGW conditions is projected as ∼ 160 mm h−1 at 27°C. The increasing rate of the extremely heavy precipitations in the present-climate condition is noticed as ∼ 3 % °C−1 and that under the PGW conditions is anticipated as ∼ 3.5 % °C−1. The increase in peak precipitation intensity and the rate of precipitation increase against temperature in future warming climate are attributed to the decrease in temperature lapse rate and increase in atmospheric water vapor and convective available potential energy. To our knowledge, this is one of the first quantitative investigations of CC scaling of extremely heavy precipitations based on case studies.

The Relationship between Precipitation and Elevation of the Watershed in the Khirthar National Range

Precipitation plays a pivotal role in the evolution of the ecosystems. Many watersheds in Pakistan and particularly in parts of Sindh are ungagged, which urge to estimate the precipitation and other parameters using feasible models for effective planning and management of water resources. Regression analysis is usually employed to understand the hydro-climatic relationships of a watershed. The present study is aimed to investigate the relationship between precipitation and elevation through developing linear regression models for various levels of precipitation data and map their spatial variability in the KNR (Khirthar National Range), Sindh, Pakistan. The precipitation data of 7 meteorological stations covering the study area were used with DEM (Digital Elevation Model) data of 90 m resolution for altitudinal trend analysis. The results of the linear regression model showed a close relationship between the precipitation of various time-scales and elevation, i.e. coefficient of determination R2 values ranging within 0.82060.9604. The correlation was significant at P&lt;0.05 for mean annual, mean monthly, and mean seasonal (Rabi) precipitation. The spatial variation in precipitation was between 127.78-697.98 mm at annual and from 10.84-58.09 mm at mean monthly level. The lapse rate of increase in precipitation with elevation was 27.03 mm per 100 m for annual and 2.24 mm per 100 m for monthly level. At seasonal level, precipitation varied from 24.17-137.87 mm during Rabi (winter) and between 105.78-525.36 mm during Kharif (summer) season. Similarly, the monsoon precipitation (July-September) ranged between 92.24359.93 mm in the study area. The higher precipitation estimated over elevated areas of the region at seasonal and annual levels needs to be harvested through adopting adequate water management techniques for improving agriculture productivity in the downstream areas.

Origins of climate model discrepancies in atmospheric shortwave absorption and global precipitation changes

Projected increases in mean precipitation are constrained by the atmospheric energy budget through radiative-convective equilibrium. However, significant differences persist between climate models on the rate of increase in precipitation per unit warming, mostly arising from the clear-sky radiative response. While the intermodel spread in clear-sky longwave cooling has been explained by climate feedbacks, the sources of spread in clear-sky shortwave heating are still unclear. This article focuses on the latter. Since water vapor contributes most of the atmospheric shortwave absorption, both intermodel differences in its spatial distribution and in radiative transfer parameterizations are plausible hypotheses for the spread. This work reestablishes the primary contribution from water vapor relative to other shortwave-absorbing species and evaluates the validity of both hypotheses. It is found that the intermodel spread in shortwave absorption change most likely originates from the radiation schemes, possibly because of simplifications induced by their low spectral resolutions.

Rising river flows and glacial mass balance in central Karakoram

Summary Field observations and geodetic measurements suggest that in the central part of the Karakoram Mountains, glaciers are either stable or expanding since 1990, in sharp contrast to glacier retreats that are prevalent in the Himalayas and adjoining high-altitude terrains of central Asia. Decreased discharge in the rivers originating from Karakoram is cited as a supporting evidence of this somewhat anomalous phenomenon. Here, in contrary to those citations, we show that, river discharge during the melting season of the glaciers in central Karakoram has increased from 1985 to 2010. We have implemented a sophisticated statistical procedure involving non-parametric tests combined with a benchmark smoothing technique that has proven to be a powerful method for empirical trend analysis to remove the stochastic component from the trend component in a time series. Melt water from winter snows is the dominant constituent of June and July flows. Glacial melts predominantly contribute to August and partially to September flows, which are controlled by monsoonal snowfall too at elevations approximately >3500 m. For all four summer months, flows increased from 1985 to 2000. August flows, which actually reflect the states of the glaciers, have continued to rise steadily after 2000 at the same rate as those did for the period 1985–2000. However, the rising trends of June and July flows changed to slightly declining trends from 2000 to 2010. These trends most likely indicate drop in winter snowfall over Karakoram and do not provide direct indications about the states of the glaciers. The rising trend of August discharge is due to change in glacial storage at a steadily decreasing rate of approximately 0.04–0.05 mm/day/year for the period 1985–2010. This rate is nearly equal to the rate of increase in precipitation during the summer months over Karakoram Mountains in recent decades as determined from the ERA-40 and GPCP precipitation datasets. Thereby, this is most plausibly, why the glacial mass balance in central Karakoram is nearly neutral. The rising river flows accompanying non-negative glacier mass balance are consistent with predicted future river flows derived from hydrologic modeling coupled with a climate projection suggesting increasing temperature and precipitation with unchanged glacier covers. This investigation reconciles two apparently contradictory observations namely rising river flows and either zero or slightly positive mass balance of central Karakoram glaciers.

The Atmospheric Energy Constraint on Global-Mean Precipitation Change

Abstract Models from phase 5 of the Coupled Model Intercomparison Project (CMIP5) robustly predict that the rate of increase in global-mean precipitation with global-mean surface temperature increase is much less than the rate of increase of water vapor. The goal of this paper is to explain in detail the mechanisms by which precipitation increase is constrained by radiative cooling. Changes in clear-sky atmospheric radiative cooling resulting from changes in temperature and humidity in global warming simulations are in good agreement with the multimodel, global-mean precipitation increase projected by GCMs (~1.1 W m−2 K−1). In an atmosphere with fixed specific humidity, radiative cooling from the top of the atmosphere (TOA) increases in response to a uniform temperature increase of the surface and atmosphere, while atmospheric cooling by exchange with the surface decreases because the upward emission of longwave radiation from the surface increases more than the downward longwave radiation from the atmosphere. When a fixed relative humidity (RH) assumption is made, however, uniform warming causes a much smaller increase of cooling at the TOA, and the surface contribution reverses to an increase in net cooling rate due to increased downward emission from water vapor. Sensitivity of precipitation changes to lapse rate changes is modest when RH is fixed. Carbon dioxide reduces TOA emission with only weak effects on surface fluxes, and thus suppresses precipitation. The net atmospheric cooling response and thereby the precipitation response to CO2-induced warming at fixed RH are mostly contributed by changes in surface fluxes. The role of clouds is discussed. Intermodel spread in the rate of precipitation increase across the CMIP5 simulations is attributed to differences in the atmospheric cooling.

Changes in precipitation and extreme precipitation in a warming environment in China

This study analyses the decadal changes in winter precipitation and extreme precipitation in a warming environment in China. The results show that, together with a trend of winter warming in China, winter precipitation and extreme precipitation in the region are also increasing. In addition, concurrent with the decadal warming shift that occurred in the mid-1980s, precipitation and extreme precipitation both increased significantly. Quantitative analysis shows that precipitation and extreme precipitation increased at rates of 9.7% and 22.6% per 1°C of surface warming in China. This rate of precipitation increase is greater than the global mean, which indicates that precipitation in China is highly sensitive to climate warming and further highlights the importance of studying regional responses to climate warming. The fact that extreme precipitation is increasing at a higher rate than precipitation implies that winter precipitation in China will increasingly be of more extreme type in the context of global warming, which could partly explain why there have recently been a number of record-breaking extreme snowfall events in China.

우리나라 강수량과 일평균기온의 시.공간적 특성변화 분석

본 연구는 1991년 이전부터 관측을 시작한 65개 기상청 관측소의 강수량과 평균기온 자료를 이용하여 2000년 이전으로 대표되는 과거 자료와 2001년 이후로 대표되는 최근 자료를 계절별로 분석하여 시 공간적 특성을 분석하였다. 관측소를 위도, 경도별로 각각 분류하여 강수량과 일평균기온의 특성을 2000년 이전과 2001년 이후에 대해 비교하였다. 또한 증감 여부를 확인하기 위해 가장 많이 사용되는 Mann-Kendall 경향성 분석 기법을 적용하였다. 위도별 분석 결과 일평균강수량의 경우 <TEX>$33^{\circ}{\sim}34^{\circ}$</TEX>(제주도)에서는 7%이상의 증가율을 보였고 남부지방에서 북부지방으로 위도가 올라갈수록 증가율이 5%~18%까지 증가하였다. 계절별로 살펴보면, 여름의 경우 위도가 증가함에 따라 강수량의 증가율도 증가하였다. 경도별 분석 결과 <TEX>$130^{\circ}{\sim}131^{\circ}$</TEX>(울릉도)에서 평균적으로 30%이상의 증가율을 보였고 서에서 동쪽으로 갈수록 증가율의 추이가 여름철의 증가 경향으로 인해 증가한다는 것을 알 수 있다. 평균 기온은 위도 <TEX>$39^{\circ}{\sim}40^{\circ}$</TEX>에서 가을철과 겨울철의 기온차가 최대 <TEX>$1.0^{\circ}C$</TEX> 이상 증가하는 추이를 보이고 있으며 경도가 <TEX>$129^{\circ}{\sim}130^{\circ}$</TEX>에서 특징적으로 기온이 상승했다. 또한 경향성 분석결과 일평균기온의 경우 일부 지역(<TEX>$34^{\circ}{\sim}35^{\circ}$</TEX>)과 여름철을 제외하면 전국적으로 봄, 가을, 겨울에 증가하는 경향이 나타났으며, 강수량의 경우 여름철에 <TEX>$36^{\circ}{\sim}38^{\circ}$</TEX>, <TEX>$126^{\circ}{\sim}130^{\circ}$</TEX> 지역에 집중적으로 증가하는 경향을 보였다. 본 연구의 결과는 최근 우리나라 기후변화 경향을 구체적으로 제시하고 있으므로 기후변화 대비 적응 연구의 기초자료로 활용될 수 있다. This study analyzed the recent changed temporal and spatial variations of precipitation and daily average temperature in the South Korea. 65 weather stations were grouped, based on their latitudes and longitudes and the recent variable temporal and spatial variations of each latitude and longitude were derived, quantitatively. In addition, the Mann-Kendall trend analysis was used to determine the tendency (upward/downward/no trend) of rainfall and temperature. From these analyses, it was shown that the precipitation of zone 1 (<TEX>$33^{\circ}-34^{\circ}$</TEX>) has increased by 7% and the rate of increase showed 5%~18% as the latitude went up. During summer, the rate of precipitation increase has increased as the latitude went up. Due to the rapid increase of summer, the rate of precipitation increase has increased as the longitude went up. On the whole, average temperature has been increased as the latitude went up. The Mann-Kendall trend analysis derived that the temperature of South Korea has increased except zone 2 (<TEX>$34^{\circ}-35^{\circ}$</TEX>)and summer period and the precipitation on latitude <TEX>$36^{\circ}{\sim}38^{\circ}$</TEX> and longitude <TEX>$126^{\circ}{\sim}130^{\circ}$</TEX> has increased during summer. Since this study showed the recent climate change trend in detail, it will be a preliminary data for the research of climate change adaptation.

Trends in precipitation on the wettest days of the year across the contiguous USA

AbstractOver the course of the 20th century, average annual precipitation for the contiguous USA has increased by nearly 10%. This increase has been described as being dominated by ‘disproportionate’ increases in extreme precipitation events. However, methodological constraints have confounded detailed interpretation of such results. Here, we briefly describe those limitations and re‐evaluate the nature of the observed precipitation changes using a method that allows for a more accurate examination of changes in the proportion of precipitation delivered in extreme daily events. We focus our analysis only on the trends in precipitation on the 10 wettest days of the year and compare the trends observed on those days with the trend in overall precipitation. When averaged across the USA, we find that the precipitation trends on the 10 wettest days of the year are not significantly different from the trend in total overall precipitation. On a regional level, in the northeast and southeast there is some evidence that the rate of precipitation increase on the wettest days exceeds that of total precipitation, whereas in the rest of the country the precipitation on the wettest days is increasing at a rate less than the increase in total precipitation. Copyright © 2004 Royal Meteorological Society