Comparison of the Tercile and Probability Distribution Formats of Seasonal Forecast Information for Climate Services Applications

Historically, seasonal regional Climate Outlook Forums around the world (eg. Greater Horn of Africa, West Africa, Southern Africa, South Asia, Southeast Asia, Caribbean and Latin America) have had a tendency to present their central findings in the format of consensus based maps of tercile probabilities of rainfall and temperature for the coming season. Tools developed at Columbia University's International Research Institute for Climate and Society (IRI) can enable a more refined understanding of the full forecast probability distribution function. This study heuristically explores the advantages and disadvantages of these two approaches from technical and user perspectives, drawing on several examples at the regional level and from Rwanda. More complex probabilistic information has been developed by IRI staff in interactive online maproom formats. While the tercile approach may convey less information than the full PDF and while it may be easier to arrive at a consensus on tercile forecasts than a full PDF, the tercile approach may over-emphasize the near normal category, may fail to convey some important information about uncertainty and may not have as direct a translation to actionable decisions on the part of the user community as may be the case if the full forecast PDF is disclosed. This being said, there may be additional technical, cost and capacity building challenges to developing robust information on the full forecast probability distribution function and translating those outputs into products that can effectively inform user decisions

Workshop report: Training and Development of Downscaled Seasonal Forecasts for Pilot Districts, Kigali, Rwanda

This report summarizes the discussions, analysis and interactions during IRI postdoctoral research scientist Asher Siebert’s one-week stay in Rwanda in late August 2016 as part of the CCAFS-Rwanda project. The overall aim of this project is help farmers in Rwanda to be better adapted to climate variability and any climate change they may face, and, in doing so, to help improve food security and agricultural outcomes. Seasonal forecasting and downscaling methods were discussed, and a particular national forecast made with the Climate Predictability Tool (CPT) and was shared, along with downscaled results in probability of exceedance format. In country meteorology participants were trained in CPT. Further discussions addressed longer-term collaborative work on both climatology and further seasonal prediction work, particularly with regard to El Nino/Southern Oscillation (ENSO) and the Indian Ocean Dipole (IOD). Discussions with experts at CIAT and the Rwanda Agriculture Board also addressed the prospect of using the Water Requirement Satisfaction Index (WRSI) as a monitoring and climate/agriculture risk management tool in the future

Training on seasonal forecasting using the IRI Climate Predictability Tool and Data Library

This report summarizes the interactions, discussions, and analyses of Asher Siebert, Post-Doctoral Research Scientist at the International Research Institute for Climate and Society (IRI), during his three-week visit to Rwanda in late August to mid- September 2017 as part of the Rwanda Climate Services for Agriculture project. The project aims to provide climate services widely throughout Rwanda and help farmers better adapt to climate variability and climate change impacts. In doing so, the project seeks to help improve agriculture outcomes and ensure food security. During the visit, trainings were held to discuss seasonal climate forecasting and downscaling methods. A particular national forecast for Rwanda along with downscaled results in probability of exceedance format for ten Rwandan districts (those in the first two phases of the project) was developed using the IRI Climate Predictability Tool (CPT). A critical component of the project’s mission is capacity building and to that end, a number of staff from the Rwanda Meteorology Agency (Météo Rwanda) were trained in CPT, the IRI Data Library, and the Météo Rwanda maprooms. Further discussions addressed longer-term collaborative work on both climatology and further seasonal prediction work, particularly with regard to El Niño - Southern Oscillation (ENSO) and the Indian Ocean Dipole (IOD). Discussions with experts at International Center for Tropical Agriculture (CIAT) and the Rwanda Agriculture Board (RAB) also focused on the newly developed water balance maprooms and the possibilities of updating these maprooms in the future

Training and Discussions on Seasonal Rainfall Forecasts for March- May 2018 in Rwanda and September- December 2017 Verification

This report describes training activities in Kigali, Rwanda, February 2018, led by Dr. Asher Siebert from the International Research Institute for Climate and Society (IRI). The training visit was part of the Rwanda Climate Services for Agriculture project, a four-year initiative (2016-2019) funded by the U.S. Agency for International Development (USAID) that seeks to transform Rwanda’s rural farming communities and national economy through climate services and improved climate risk management. The main objective of the training visit was to collaborate on seasonal rainfall forecasts for MAM 2018 in Rwanda and SOND 2017 verification

Impact of population growth and population ethics on climate change mitigation policy

Future population growth is uncertain and matters for climate policy: higher growth entails more emissions and means more people will be vulnerable to climate-related impacts. We show that how future population is valued importantly determines mitigation decisions. Using the Dynamic Integrated Climate-Economy model, we explore two approaches to valuing population: a discounted version of total utilitarianism (TU), which considers total wellbeing and is standard in social cost of carbon dioxide (SCC) models, and of average utilitarianism (AU), which ignores population size and sums only each time period’s discounted average wellbeing. Under both approaches, as population increases the SCC increases, but optimal peak temperature decreases. The effect is larger under TU, because it responds to the fact that a larger population means climate change hurts more people: for example, in 2025, assuming the United Nations (UN)-high rather than UN-low population scenario entails an increase in the SCC of 85% under TU vs. 5% under AU. The difference in the SCC between the two population scenarios under TU is comparable to commonly debated decisions regarding time discounting. Additionally, we estimate the avoided mitigation costs implied by plausible reductions in population growth, finding that large near-term savings ($billions annually) occur under TU; savings under AU emerge in the more distant future. These savings are larger than spending shortfalls for human development policies that may lower fertility. Finally, we show that whether lowering population growth entails overall improvements in wellbeing—rather than merely cost savings—again depends on the ethical approach to valuing population

Advancing the use of gridded, online climate information for risk management in the Horn of Africa

This report summarizes the discussions, deliberations and recommendations made during the side event, Advancing the use of gridded, online climate information for risk management in the Horn of Africa, to the Forty Eighth Greater Horn of Africa Climate Outlook Forum (GHACOF 48). This event was co-organized by the Climate Services for Africa project—led by the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS)—and the Weather and Climate Information Services for Africa (WISER) - qEnhancing National Climate Services initiative (ENACTS), that was held on 13 February 2018 in Mombasa, Kenya. The main aim of the event was to advance shared understanding, between climate information users and providers on how the GHACOF process and member country National Meteorological and Hydrological Services (NMHSs) can support more effective use of climate information. The meeting was geared towards raising awareness on recent developments in climate information products developed for the agriculture and food security sector through the ENACTS approach and demonstrate ICPAC capabilities to support member countries in the development of gridded historical and seasonal forecast climate information Maproom products tailored to user needs. Agro-climatic variables showcased included rainfall onset dates (both in historical and forecast mode), cessation dates, historical wet and dry spells, and rainfall intensity. The meeting was also intended to bring an informed agriculture user perspective into a discussion with ICPAC and NMHSs about how the GHACOF process can be made more useful for the agriculture and food security sector. The workshop brought together representatives from member country NMHSs, experienced agricultural and food security users and champions of climate information, ICPAC, WMO, and WISER and Climate Services for Africa project partners. Workshop participants appreciated the importance of these agro-climatic variables in making timely and informed decisions

Seasonal predictability of Ethiopian Kiremt rainfall and forecast skill of ECMWF's SEAS5 model

Predictability of Ethiopian Kiremt rainfall (June to September: JJAS) and forecast skill of the European Centre for MediumRange Weather Forecasts (ECMWF) fifth-generation seasonal forecast system 5 (SEAS5) is explored during 1981–2019. The first empirical orthogonal function of observed rainfall explains 50.6% of the total variability and is characterized by positive rainfall anomalies largely confined over the northwestern and central-western regions of Ethiopia. Consequently, a Kiremt rainfall index (KRI) is defined for this region. The correlation coefficient (CC) between the observed and predicted KRI is 0.68 and 0.53 for May and April starts, respectively. Composite analysis of sea surface temperature (SST) and lowerlevel circulation based on excess and deficit years of Kiremt rains shows that the El Niño Southern–Oscillation is the main modulator of the Kiremt rainfall variability. The CC between KRI and Niño3.4 index is − 0.62, indicating that El Niño is accompanied by below-normal Kiremt rainfall, while La Niña is accompanied by above-normal amounts. The fifth generation of ECMWF atmospheric reanalysis (ERA5) shows that excess (deficit) Kiremt rainfall anomalies are associated with an anomalous low (high) pressure centered over northeast Arabian Peninsula and an anomalous in-phase (reverse) low-level Somali Jet. SEAS5 reproduces the spatial and temporal components of observed Kiremt rainfall variability, including the main climatic features associated with excess and deficit Kiremt rainfall in May and April starts. However, certain important observed features like above-normal SSTs in the Gulf of Guinea are not well predicted. Results indicate that Kiremt rains has some potential predictability and SEAS5 shows a moderate forecast skill. Probabilistic analysis shows highest values where predictability and deterministic skill are also highest

Post-operative atrial fibrillation: a maze of mechanisms

Post-operative atrial fibrillation (POAF) is one of the most frequent complications of cardiac surgery and an important predictor of patient morbidity as well as of prolonged hospitalization. It significantly increases costs for hospitalization. Insights into the pathophysiological factors causing POAF have been provided by both experimental and clinical investigations and show that POAF is ‘multi-factorial’. Facilitating factors in the mechanism of the arrhythmia can be classified as acute factors caused by the surgical intervention and chronic factors related to structural heart disease and ageing of the heart. Furthermore, some proarrhythmic mechanisms specifically occur in the setting of POAF. For example, inflammation and beta-adrenergic activation have been shown to play a prominent role in POAF, while these mechanisms are less important in non-surgical AF. More recently, it has been shown that atrial fibrosis and the presence of an electrophysiological substrate capable of maintaining AF also promote the arrhythmia, indicating that POAF has some proarrhythmic mechanisms in common with other forms of AF. The clinical setting of POAF offers numerous opportunities to study its mechanisms. During cardiac surgery, biopsies can be taken and detailed electrophysiological measurements can be performed. Furthermore, the specific time course of POAF, with the delayed onset and the transient character of the arrhythmia, also provides important insight into its mechanisms

A Festschrift Recital: Celebrating Dr. Carol Kimball\u27s 36 Years at the University of Nevada, Las Vegas

Program listing performers and works performe