Addressing Uncertainties in Projected IDF Relationships under Climate Change

2020 ◽  
Author(s):  
Kumar Puran Tripathy ◽  
Pradeep Mujumdar
Keyword(s):  
Climate Change ◽  
Small Samples ◽  
Mcmc Method ◽  
Ensemble Averaging ◽  
Major Objective ◽  
Gev Distribution ◽  
Temporal Disaggregation ◽  
Intensity Duration Frequency ◽  
Invariance Theory

<p>The Intensity-Duration-Frequency (IDF) relationships are commonly used in urban hydrologic designs. A major source of uncertainty arises due to small samples of data and use of multiple GCMs, in developing the IDF for future periods. A major objective of this study is to address uncertainties in the IDF relationships for future periods, under climate change. The study proposes a Bayesian method for addressing the parameter uncertainty in the Generalized Extreme Value (GEV) distribution for the Annual Maximum Series (AMS). Uncertainties due to the use of multiple GCMs are addressed through the Reliable Ensemble Averaging (REA) method. The posterior distributions of the three parameters of GEV distribution are obtained using Markov Chain Monte Carlo (MCMC) method. Twenty-three CMIP5 GCMs with four RCPs are considered for studying the effect of climate change on the IDF relationship for the case study of Bangalore, India. Change Factor Method (CFM) is used for spatially downscaling the projected time series of precipitation and scale-invariance theory is used for temporal disaggregation. Results are compared across different CFM schemes considering multiple bin sizes. Uncertainties in design intensities are quantified through probabilistic IDF relationships.</p>

scholarly journals Climate change impacts on intensity duration frequency curves of precipitation: A case study of Shiraz synoptic station, Iran

2021 ◽  
Vol 21 (2) ◽  
pp. 159-165
Author(s):  
A.ROSHAN ◽  
H. SEDGHI ◽  
R.A.SHARIFAN ◽  
J.PORHEMMAT
Keyword(s):  
Climate Change ◽  
Type Equation ◽  
Gumbel Distribution ◽  
Climate Change Impacts ◽  
Synoptic Station ◽  
Standard Design ◽  
The Future ◽  
Idf Curves ◽  
Intensity Duration Frequency

Intensity-duration-frequency (IDF) curves are among the standard design tools for many engineering applications such as urban drainage management. Since climate change may considerably affect precipitation, updating of IDF curves is highly necessary. The present study aims to examine the impacts of climate change on IDF curves of Shiraz synoptic station using downscaled outputs of Hadcm3 AOGCM under various emission scenarios (A1B, A2,B1) applying larswg-5 model for the period of 2046 to 2065. The fitted Gumbel distribution was used to estimate the maximum short-term precipitation quantiles in the base period (1968-2000) and the verified empirical Bell type equation was used for the future period. The results show that the mean of maximum daily precipitation and annual precipitation will decrease in the future. Also, the maximum precipitation intensities up to 60 min duration will reducefrom 0.15 mm hr-1 to about 10.79 mm hr-1 compared to the observed period in all returns periods and various scenarios. Overall, there were no tangible changes in intensities for durations higher than 60 min. The highest reduction in precipitation intensity would be at the 20 min duration with 100-year return period in the A2 scenario.

Understanding the Outcomes of Climate Change Campaigns in the Australian Environmental Movement

2019 ◽  
Vol 3 (1) ◽  
pp. 1-9
Author(s):  
Robyn Gulliver ◽  
Kelly S. Fielding ◽  
Winnifred Louis
Keyword(s):  
Climate Change ◽  
Collective Action ◽  
Environmental Advocacy ◽  
Personal Support ◽  
Governmental Organizations ◽  
Collective Response ◽  
Non Governmental Organizations ◽  
Advocacy Network ◽  
Australian Climate

Climate change is a global problem requiring a collective response. Grassroots advocacy has been an important element in propelling this collective response, often through the mechanism of campaigns. However, it is not clear whether the climate change campaigns organized by the environmental advocacy groups are successful in achieving their goals, nor the degree to which other benefits may accrue to groups who run them. To investigate this further, we report a case study of the Australian climate change advocacy sector. Three methods were used to gather data to inform this case study: content analysis of climate change organizations’ websites, analysis of website text relating to campaign outcomes, and interviews with climate change campaigners. Findings demonstrate that climate change advocacy is diverse and achieving substantial successes such as the development of climate change-related legislation and divestment commitments from a range of organizations. The data also highlights additional benefits of campaigning such as gaining access to political power and increasing groups’ financial and volunteer resources. The successful outcomes of campaigns were influenced by the ability of groups to sustain strong personal support networks, use skills and resources available across the wider environmental advocacy network, and form consensus around shared strategic values. Communicating the successes of climate change advocacy could help mobilize collective action to address climate change. As such, this case study of the Australian climate change movement is relevant for both academics focusing on social movements and collective action and advocacy-focused practitioners, philanthropists, and non-governmental organizations.

Sign in / Sign up

Export Citation Format

Share Document