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Use of Climate Information in Malaria Stratification/Early Warning Systems/Impact Assessment for Malaria Interventions
A report on the training workshop and stakeholder meeting hosted by the Tanzania Meteorological Agency in Dar es Salaam, Tanzania October 16th-18th 2013
Spatial and Temporal Analysis of Rainfall and Temperature Extreme Indices in Tanzania
Climate extreme indices in Tanzania for the period 1961-2015 are analyzed
using quality controlled daily rainfall, maximum and minimum temperatures
data. RClimdex and National Climate Monitoring Products (NCMP) software
developed by the commission for Climatology of the World Meteorological
Organization (WMO) were used for the computation of the indices at the respective
stations at monthly and annual time scales. The trends of the extreme
indices averaged over the country were computed and tested for statistical
significance. Results showed a widespread statistical significant increase in
temperature extremes consistent with global warming patterns. On average,
the annual timescale indicate that mean temperature anomaly has increased
by 0.69˚C, mean percentage of warm days has increased by 9.37%, and mean
percentage of warm nights has increased by 12.05%. Mean percentage of
cold days and nights have decreased by 7.64% and 10.00% respectively. A
non-statistical significance decreasing trends in rainfall is depicted in large
parts of the country. Increasing trend in percentage of warm days and warm
nights is mostly depicted over the eastern parts of the country including areas
around Kilimanjaro, Dar-es-Salaam, Zanzibar, Mtwara, and Mbeya regions.
Some parts of the Lake Victoria Basin are also characterized by increasing
trend of warm days and warm nights. However, non-statistical significant decreasing
trends in the percentage of warm days and warm nights are depicted
in the western parts of the country including Tabora and Kigoma regions and
western side of the lake Victoria. These results indicate a clear dipole pattern
in temperature dynamics between the eastern side of the country mainly influenced
by the Indian Ocean and the western side of the country largely influenced
by the moist Congo air mass associated with westerly winds. The results
also indicate that days and nights are both getting warmer, though, the
warming trend is much faster in the minimum temperature than maximum
temperature.The paper is publishedThe authors wish to thank The Tanzania Meteorological Agency for providing
data used in this study and WMO for providing guidance in the analysis of climate
extreme in climate time series
Sea Level Variability and Change
Land surface albedo represents the fraction of solar radiation scattered backward by land surfaces.
In the presence of vegetation, surface albedo results from complex nonlinear radiation transfer processes
determining the amount of radiation that is scattered by the vegetation and its background, transmitted
through the vegetation layer, or absorbed by the vegetation layer and its background. Anomalies in mid- and high
latitude regions of the Northern Hemisphere result
mainly from interannual variations in snow cover
extent and duration in winter and spring. The large
negative anomalies over the United States reflect the
lack of snowfall and snowpack over the Rockies, the
Midwest, and much of the eastern half of the country.JRC.H.7-Climate Risk Managemen
State of the Climate in 2012
For the first time in serveral years, the El Nino-Southern Oscillation did not dominate regional climate conditions around the globe. A weak La Ni a dissipated to ENSOneutral conditions by spring, and while El Nino appeared to be emerging during summer, this phase never fully developed as sea surface temperatures in the eastern conditions. Nevertheless, other large-scale climate patterns and extreme weather events impacted various regions during the year. A negative phase of the Arctic Oscillation from mid-January to early February contributed to frigid conditions in parts of northern Africa, eastern Europe, and western Asia. A lack of rain during the 2012 wet season led to the worst drought in at least the past three decades for northeastern Brazil. Central North America also experienced one of its most severe droughts on record. The Caribbean observed a very wet dry season and it was the Sahel's wettest rainy season in 50 years. Overall, the 2012 average temperature across global land and ocean surfaces ranked among the 10 warmest years on record. The global land surface temperature alone was also among the 10 warmest on record. In the upper atmosphere, the average stratospheric temperature was record or near-record cold, depending on the dataset. After a 30-year warming trend from 1970 to 1999 for global sea surface temperatures, the period 2000-12 had little further trend. This may be linked to the prevalence of La Ni a-like conditions during the 21st century. Heat content in the upper 700 m of the ocean remained near record high levels in 2012. Net increases from 2011 to 2012 were observed at 700-m to 2000-m depth and even in the abyssal ocean below. Following sharp decreases in to the effects of La Ni a, sea levels rebounded to reach records highs in 2012. The increased hydrological cycle seen in recent years continued, with more evaporation in drier locations and more precipitation in rainy areas. In a pattern that has held since 2004, salty areas of the ocean surfaces and subsurfaces were anomalously salty on average, while fresher areas were anomalously fresh. Global tropical cyclone activity during 2012 was near average, with a total of 84 storms compared with the 1981-2010 average of 89. Similar to 2010 and 2011, the North Atlantic was the only hurricane basin that experienced above-normal activity. In this basin, Sandy brought devastation to Cuba and parts of the eastern North American seaboard. All other basins experienced either near-or below-normal tropical cyclone activity. Only three tropical cyclones reached Category 5 intensity-all in Bopha became the only storm in the historical record to produce winds greater than 130 kt south of 7 N. It was also the costliest storm to affect the Philippines and killed more than 1000 residents. Minimum Arctic sea ice extent in September and Northern Hemisphere snow cover extent in June both reached new record lows. June snow cover extent is now declining at a faster rate (-17.6% per decade) than September sea ice extent (-13.0% per decade). Permafrost temperatures reached record high values in northernmost Alaska. A new melt extent record occurred on 11-12 July on the Greenland ice sheet; 97% of the ice sheet showed some form of melt, four times greater than the average melt for this time of year. The climate in Antarctica was relatively stable overall. The largest maximum sea ice extent since records begain in 1978 was observed in September 2012. In the stratosphere, warm air led to the second smallest ozone hole in the past two decades. Even so, the springtime ozone layer above Antarctica likely will not return to its early 1980s state until about 2060. Following a slight decline associated with the global 2 emissions from fossil fuel combustion and cement production reached a record 9.5 +/- 0.5 Pg C in 2011 and a new record of 9.7 +/- 0.5 Pg C is estimated for 2012. Atmospheric CO2 concentrations increased by 2.1 ppm in 2012, to 392.6 ppm. In spring 2012, 2 concentration exceeded 400 ppm at 7 of the 13 Arctic observation sites. Globally, other greenhouse gases including methane and nitrous oxide also continued to rise in concentration and the combined effect now represents a 32% increase in radiative forcing over a 1990 baseline. Concentrations of most ozone depleting substances continued to fall