Evaluation of DSSAT-MANIHOT-Cassava model to determine potential irrigation benefits for cassava in Jamaica

Cassava (Manihot esculenta Crantz) is an important food crop, especially in developing countries, because of its resilience and ability to grow in conditions generally inhospitable for other crops. However, tropical crops like cassava are not as frequently modeled compared with crops from temperate locations. The objective of this research was to calibrate the CSM-MANIHOT-Cassava model of the Decision Support System for Agrotechnology Transfer, DSSAT beta v4.8 and use the model to evaluate the potential benefits of irrigation on yield. We established two field trials with two water treatments (rainfed and irrigated) and four cultivars that had not been studied previously. We simulated in-season biomass and end-of-season yield, evaluating the model performance with different statistical measures. There was good agreement between simulated and measured values; the best results showed a deviation of 9.7%, normalized RMSE of 18%, and d-index of 0.98 for biomass, with corresponding values of 11, 24, and 0.98, respectively, for yield. Good simulations of yield correlated with accurate simulations for leaf area index and harvest index. The varieties showed differential responses to irrigation, suggesting that there are diverse levels of drought tolerance even within the same environmental condition

The state of the Martian climate

60°N was +2.0°C, relative to the 1981–2010 average value (Fig. 5.1). This marks a new high for the record. The average annual surface air temperature (SAT) anomaly for 2016 for land stations north of starting in 1900, and is a significant increase over the previous highest value of +1.2°C, which was observed in 2007, 2011, and 2015. Average global annual temperatures also showed record values in 2015 and 2016. Currently, the Arctic is warming at more than twice the rate of lower latitudes

State of the climate in 2018

In 2018, the dominant greenhouse gases released into Earth’s atmosphere—carbon dioxide, methane, and nitrous oxide—continued their increase. The annual global average carbon dioxide concentration at Earth’s surface was 407.4 ± 0.1 ppm, the highest in the modern instrumental record and in ice core records dating back 800 000 years. Combined, greenhouse gases and several halogenated gases contribute just over 3 W m−2 to radiative forcing and represent a nearly 43% increase since 1990. Carbon dioxide is responsible for about 65% of this radiative forcing. With a weak La Niña in early 2018 transitioning to a weak El Niño by the year’s end, the global surface (land and ocean) temperature was the fourth highest on record, with only 2015 through 2017 being warmer. Several European countries reported record high annual temperatures. There were also more high, and fewer low, temperature extremes than in nearly all of the 68-year extremes record. Madagascar recorded a record daily temperature of 40.5°C in Morondava in March, while South Korea set its record high of 41.0°C in August in Hongcheon. Nawabshah, Pakistan, recorded its highest temperature of 50.2°C, which may be a new daily world record for April. Globally, the annual lower troposphere temperature was third to seventh highest, depending on the dataset analyzed. The lower stratospheric temperature was approximately fifth lowest. The 2018 Arctic land surface temperature was 1.2°C above the 1981–2010 average, tying for third highest in the 118-year record, following 2016 and 2017. June’s Arctic snow cover extent was almost half of what it was 35 years ago. Across Greenland, however, regional summer temperatures were generally below or near average. Additionally, a satellite survey of 47 glaciers in Greenland indicated a net increase in area for the first time since records began in 1999. Increasing permafrost temperatures were reported at most observation sites in the Arctic, with the overall increase of 0.1°–0.2°C between 2017 and 2018 being comparable to the highest rate of warming ever observed in the region. On 17 March, Arctic sea ice extent marked the second smallest annual maximum in the 38-year record, larger than only 2017. The minimum extent in 2018 was reached on 19 September and again on 23 September, tying 2008 and 2010 for the sixth lowest extent on record. The 23 September date tied 1997 as the latest sea ice minimum date on record. First-year ice now dominates the ice cover, comprising 77% of the March 2018 ice pack compared to 55% during the 1980s. Because thinner, younger ice is more vulnerable to melting out in summer, this shift in sea ice age has contributed to the decreasing trend in minimum ice extent. Regionally, Bering Sea ice extent was at record lows for almost the entire 2017/18 ice season. For the Antarctic continent as a whole, 2018 was warmer than average. On the highest points of the Antarctic Plateau, the automatic weather station Relay (74°S) broke or tied six monthly temperature records throughout the year, with August breaking its record by nearly 8°C. However, cool conditions in the western Bellingshausen Sea and Amundsen Sea sector contributed to a low melt season overall for 2017/18. High SSTs contributed to low summer sea ice extent in the Ross and Weddell Seas in 2018, underpinning the second lowest Antarctic summer minimum sea ice extent on record. Despite conducive conditions for its formation, the ozone hole at its maximum extent in September was near the 2000–18 mean, likely due to an ongoing slow decline in stratospheric chlorine monoxide concentration. Across the oceans, globally averaged SST decreased slightly since the record El Niño year of 2016 but was still far above the climatological mean. On average, SST is increasing at a rate of 0.10° ± 0.01°C decade−1 since 1950. The warming appeared largest in the tropical Indian Ocean and smallest in the North Pacific. The deeper ocean continues to warm year after year. For the seventh consecutive year, global annual mean sea level became the highest in the 26-year record, rising to 81 mm above the 1993 average. As anticipated in a warming climate, the hydrological cycle over the ocean is accelerating: dry regions are becoming drier and wet regions rainier. Closer to the equator, 95 named tropical storms were observed during 2018, well above the 1981–2010 average of 82. Eleven tropical cyclones reached Saffir–Simpson scale Category 5 intensity. North Atlantic Major Hurricane Michael’s landfall intensity of 140 kt was the fourth strongest for any continental U.S. hurricane landfall in the 168-year record. Michael caused more than 30 fatalities and $25 billion (U.S. dollars) in damages. In the western North Pacific, Super Typhoon Mangkhut led to 160 fatalities and$6 billion (U.S. dollars) in damages across the Philippines, Hong Kong, Macau, mainland China, Guam, and the Northern Mariana Islands. Tropical Storm Son-Tinh was responsible for 170 fatalities in Vietnam and Laos. Nearly all the islands of Micronesia experienced at least moderate impacts from various tropical cyclones. Across land, many areas around the globe received copious precipitation, notable at different time scales. Rodrigues and Réunion Island near southern Africa each reported their third wettest year on record. In Hawaii, 1262 mm precipitation at Waipā Gardens (Kauai) on 14–15 April set a new U.S. record for 24-h precipitation. In Brazil, the city of Belo Horizonte received nearly 75 mm of rain in just 20 minutes, nearly half its monthly average. Globally, fire activity during 2018 was the lowest since the start of the record in 1997, with a combined burned area of about 500 million hectares. This reinforced the long-term downward trend in fire emissions driven by changes in land use in frequently burning savannas. However, wildfires burned 3.5 million hectares across the United States, well above the 2000–10 average of 2.7 million hectares. Combined, U.S. wildfire damages for the 2017 and 2018 wildfire seasons exceeded $40 billion (U.S. dollars)

Climate Models, Interpreting Results, and Impacts

This presentation focused on climate modeling and included the methods used and the results that come from climate models. The presentation focused on interpretation of the models rather than the detailed "how to" use of models. The focus was again the Caribbean region.Climate Change, Water Management

Français

Caribbean economies, lifestyles, activities, practices and operational cycles are intricately linked to climate, making them vulnerable to its variations and/or changes. As examples, climate extremes impact agriculture, fisheries, health, tourism, water availability, recreation, and energy usage, among other things. There is however limited incorporation of climate information in the long term developmental plans and policies of the region. This is in part due to a knowledge deficit about climate change, it’s likely manifestation in the region and the possible impact on Caribbean societies. In this paper, a review of the growing bank of knowledge about Caribbean climate science; variability and change is undertaken. Insight is offered into the basic science of climate change, past trends and future projections for Caribbean climate, and the possible implications for the region. In the end a case is made for a greater response to the threats posed by climate change on the basis of the sufficiency of our current knowledge of Caribbean climate science. A general profile of what the response may look like is also offered.Las economías de los países caribeños, los estilos de vida, las actividades, y las prácticas y ciclos operativos están íntimamente ligados al clima, por lo que estas sociedades son vulnerables a los cambios y/o las variaciones del mismo. Los extremos climáticos afectan la agricultura, pesca, salud, turismo, disponibilidad de agua, recreación, uso de energía, para sólo mencionar algunos ejemplos. Sin embargo, no se incorpora mucha información acerca del clima en los planes de desarrollo a largo plazo ni en el desarrollo de políticas públicas de la región. Esto se debe en parte a un desconocimiento acerca del cambio climático, su manifestación probable en la región y su posible impacto en las sociedades caribeñas. Este artículo presenta una revisión del creciente banco de conocimiento sobre la ciencia climática caribeña; sus cambios y variabilidad. Se ofrece una breve descripción de los fundamentos de la ciencia que estudia el cambio climático, las tendenciaspasadas y las proyecciones futuras para el clima en el Caribe, así como los posibles impactos para la región. Al final se aboga por que haya una mayor respuesta a las amenazas que representan los cambios climáticos entendiendo que la ciencia climática caribeña cuenta con suficiente información actualizada. Además, se presenta un perfil general de cómo podría ser tal respuesta.Les économies des pays caribéens, les modes de vie, les activités, les pratiques et les cycles opérationnels sont intimement liés au climat, à cause de la vulnérabilité de ces sociétés face aux changements climatiques et/ou aux variations de ces deniers. Les extrêmes climatiques affectent l’agriculture, la pêche, la santé, le tourisme, l’approvisionnement en eau, la consommation d’énergie, pour ne citer que quelques exemples. Cependant, peu d’importance est accordé au climat dans les plans de développement à long terme, ni dans le développement des politiques publiques de la région. Ceci est dû en partie à un manque de connaissance sur le changement climatique, sa probable manifestation dans la région et son possible impact dans les sociétés caribéennes. Cet article présente une vue d’ensemble de la croissante banque de connaissances sur la science du climat caribéen ; ses changements et ses variabilités. On propose une brève description des éléments fondamentaux de la science qui étudie le changement climatique, les tendances passées et les projections futures pour le climat dans la Caraïbe, ainsi que les menaces que représentent les changements climatiques, tout en considérant que tenant compte la science climatique caribéenne dispose suffisamment de données récentes. En outre, on présente un aperçu général de la façon dont le problème climatique pourrait être abordé

Frequency analysis, infilling and trends for extreme precipitation for Jamaica (1895–2100)

Study region: The island of Jamaica. Study Focus: Existing intensity duration frequency (IDF) curves for Jamaica were calculated over 20 years ago for two stations using an annual maxima series (AMS) that is 30 years long. The goodness of fit for the IDF curves is no longer available, and trends have not been accounted for in the series. Data recovery efforts undertaken in this study facilitate a re-examination and comparison of the existing IDF curves with new curves derived from an extended AMS from 1895 to 2010. In extending the data, gaps in the short durations (5 min to 12 h) AMS were filled using an empirical formula and gaps in the long durations (2–10 days) were filled by artificial neural network (ANN) downscaling. Analysis included an examination of frequency analysis configuration for varying probability distribution functions (PDF), plotting point functions (PPF) and parameter estimation methods (PEM). The study determines PDF as the most important factor in the configuration of the frequency analysis. Infilling and extension are also shown to reduce the biases, improve the frequency analysis and yield higher predicted intensities. New hydrological insights for the region: Temporal trends in location,scale and shape parameters for each station were also examined and lin-early projected to 2100. Increases in 2100 intensities vary from 27% to 59%for the 100 years return period (RP) as a result of increases in the variability. Keywords: Frequency analysis, Climate change, Extreme precipitation, Artificial neural network, Intensity duration frequency curve, Jamaic

Characterization of Future Caribbean Rainfall and Temperature Extremes across Rainfall Zones

End-of-century changes in Caribbean climate extremes are derived from the Providing Regional Climate for Impact Studies (PRECIS) regional climate model (RCM) under the A2 and B2 emission scenarios across five rainfall zones. Trends in rainfall, maximum temperature, and minimum temperature extremes from the RCM are validated against meteorological stations over 1979–1989. The model displays greater skill at representing trends in consecutive wet days (CWD) and extreme rainfall (R95P) than consecutive dry days (CDD), wet days (R10), and maximum 5-day precipitation (RX5). Trends in warm nights, cool days, and warm days were generally well reproduced. Projections for 2071–2099 relative to 1961–1989 are obtained from the ECHAM5 driven RCM. Northern and eastern zones are projected to experience more intense rainfall under A2 and B2. There is less consensus across scenarios with respect to changes in the dry and wet spell lengths. However, there is indication that a drying trend may be manifest over zone 5 (Trinidad and northern Guyana). Changes in the extreme temperature indices generally suggest a warmer Caribbean towards the end of century across both scenarios with the strongest changes over zone 4 (eastern Caribbean)