Livestock Transactions as Coping Strategies in Zambia:New Evidence from High-Frequency Panel Data

This study re-examines the buffer stock hypothesis regarding livestock by taking into account differences in wealth level, asset types, and periods after a shock. This paper takes advantage of a unique panel data set of agricultural households in Southern Province, Zambia. The data were collected by weekly interviews of 48 sample households from November 2007 to December 2009, covering two crop years in which an unusually heavy rainfall event took place. If we consider delayed responses to the heavy rain shock, our econometric analyses support the buffer stock hypothesis for cattle as well as small livestock. Overall, this paper suggests that conventional annual data sets used by existing literature may miss the period-dependent transactions of assets after a shock.Asset smoothing, Buffer stock, Weather risk, Livestock, Sub-Saharan Africa

Strongly Negative Correlation between Monthly Mean Temperatures in April and August since 1998 in Northern Japan

Monthly mean temperatures for April and August have been strongly and negatively correlated from 1998 to 2011 in northern Japan. When monthly mean temperatures in April were either significantly below or significantly above normal, the temperatures in the following August had the opposite anomalies. We attribute this seasonal behavior of temperatures to a displacement of the core of upper-level westerly winds. When monthly mean temperature was higherthan normal in August, the subtropical jet stream had been strengthened in April and a continental polar air mass affected northern Japan in April. In August of that year, if a jet located north of Japan moved further north, Japan was covered by a maritime tropical air mass, and a maritime polar air mass rarely affected summer weather in northern Japan. In the opposite case, when temperatures were cool in August and warm in April, we inferred that the jet had been weak and the continental polar air mass did not move south and affect northern Japan in April; thus, in August the jet shifted southward and the maritime polar air mass could affect summer weather. An empirical orthogonal function analysis of the 200-hPa height field revealed that two principal component modes were associated with the anomalous temperatures in these two months. On the basis of these results, we identify these modes as the cause of upper level westerly wind variations on the northern hemispheric scale. Based on a singular value decomposition analysis of the 200-hPa height field and the sea surface temperature, the year 1998 marked one of the several pronounced climatic shifts of the last century

Livestock Transactions as Coping Strategies in Zambia: New Evidence from High-Frequency Panel Data

This study re-examines the buffer stock hypothesis regarding livestock by taking into account differences in wealth level, asset types, and periods after a shock. This paper takes advantage of a unique panel data set of agricultural households in Southern Province, Zambia. The data were collected by weekly interviews of 48 sample households from November 2007 to December 2009, covering two crop years in which an unusually heavy rainfall event took place. If we consider delayed responses to the heavy rain shock, our econometric analyses support the buffer stock hypothesis for cattle as well as small livestock. Overall, this paper suggests that conventional annual data sets used by existing literature may miss the period-dependent transactions of assets after a shock.Asset Smoothing, Buffer Stock, Weather Risk, Livestock, Sub-Saharan Africa

Why Does a Larch Scrub Community Establish around Oniwa on the Northwestern Slope of Mount Fuji? : Experiencing the Fascination Again of a Tour of the Ochu-do Trail

Mount Fuji is a relatively young mountain, which erupted intermittently until 1707. Thetree limit on Mount Fuji is composed of larches (Larix leptolepis). The limit ranges from 1,400 to 2,900 meters in altitude, depending on the slope. Around Oniwa on the northwestern slope of Mount Fuji, a larch scrub community is scattered in patches, forming an island, where the tree line is 2,650 meters. All of the larches are severely deformed toward the northeast due to strong winds. Factors maintaining the larch scrub are examined referring to tree size and tree age. Tree size decreases rapidly above an altitude of 2,390 meters on the northwestern slope, where the forest limit is located. On this slope, we can observe both a group of trees showing a stronger tendency toward growth in terms of height and another group growth in terms of diameter. These growth patterns change depending on the altitude; that is, the higher the altitude, the greater the diameter, and the lower the altitude, the greater the height. On the other hand, the relationships between tree size and tree age show a tendency at lower altitudes of older trees having greater heights, and at higher altitudes of older trees having greater diameter, but not heights. These facts suggest that a larch scrub community forms by controlling exposure to the severe environment. This is also in accord with the observation of older trees having greaterdeformation. It is considered that embolism is a plausible cause controlling tree size, especially tree height, because frost action with severe transpiration frequently occurs on this slope. As a result, a scrub formation would be fixed. This explanation of the growth mechanism of the land scape around Oniwa on the northwestern part of the Ochu-do trail running along the side of Mount Fuji will assist eco- and geo-tourism development on the Ochu-do

Diurnal and Seasonal Relationships between Nocturnal Cooling and Meteorological Parameters: Validation Using Observation Data

We investigated diurnal and seasonal relationships between nocturnal cooling and meteorological parameters by using 5-year observation data from the NARO Tohoku Agricultural Research Center, Japan. Multiple regression analysis between nocturnal cooling (7J10C) and meteorological parameters (total net radiation, Rntol; total weak-wind duration, Wdw{, and snow depth, SD) revealed that Rntot and l¥dloi dominantly contributed to Tnoc. Diurnal relationships among Tnoc, Rnwu and WdM suggested that a strong temperature drop occurred not only on calm nights but also at nights when weak wind conditions lasted at least a few hours. In addition, in the warm season, correlation coefficients between 7;ioc and ^«tot were nearly the same in every Wdlol category. In the cold season,however, those coefficients varied with Wdlm. We attributed this difference to the strong, synoptic-scale winds that accompanied cold and warm advection in the cold season

MIROC5 predictions of Yamase (cold northeasterly winds causing cool summers in northern Japan)

Cold northeasterly winds, called Yamase, which cause the summertime weather of northern Japan to be unusually cool, have often damaged the rice crop in northern Japan, both historically and recently. To estimate future Yamase event occurrences, we used the new version of the MIROC5 atmosphere-ocean general circulation model and predicted the frequency of future Yamase events from the pressure difference index (pressure difference between Wakkanai and Sendai; PDWS). In a 20th-century experiment (1980-2005), the PDWS simulated by the MIROC5 model reproduced well the Yamase events in the JRA-25 reanalysis data. In a future climate experiment (2006-2100), the predicted occurrence frequency of Yamase events is low around the 2030s and from the 2080s onward, but in other periods, Yamase events are predicted to occur at about the same frequency as during the 20th-century experiment (1980-2005). Therefore, even under global warming, Yamase winds can be expected to affect agriculture in northern Japan in the 21 st century

Analysis of Meteorological Measurements made over Three Rainy Seasons and Rainfall Simulations in Sinazongwe District, Southern Province, Zambia

Zambia has frequently been affected by abnormal weather and droughts. Our research focused on the type of meteorological data required to assist farmers\u27 efforts to avoid the risks associated with these weather conditions. We conducted local meteorological observations from September 2007 to August 2010 at three sites in Sinazongwe District, Zambia. The three rainy seasons of this period coincided in sequence with La Niña (normal) and El Niño conditions. The mean annual precipitation for the three years of our study exceeded 1200 mm, which was considerably more than the regional annual average rainfall from 1970 to 2000 of a round 800 mm per year. We used detailed analyses of intraseasonal variations in other meteorological elements to attempt to explain the high precipitation.Local circulation dominated in our research area, while heavy rain induced by convection in the afternoon and night might account for precipitation exceeding the norm. We numerically simulated meteorological conditions over the past decade to determine whether the annual precipitation observed since September 2007 indeed exceeded the norm. lntra-seasonal variations in precipitation, such as high rainfall in December during the 2007/2008 rainy season, a gradual increase in cumulative precipitation through 2008/2009, and high rainfall in February in the 2009/2010 rainy season were possibly controlled by El Niño - Southern Oscil lation. Our results suggest that annual variations in precipitation are common in this area and that the precipitation we observed did not necessarilyexceed the norm

Estimation of cool summer damage in the Tohoku region based on the MRI AGCM

We analyzed the impact of climate change due to global warming on the risk of cool summer damage to paddy rice in the Tohoku region of Japan. We downscaled the atmospheric general circulation model of the Meteorological Research Institute(MRI AGCM) to 10 km, and we used monthly average temperatures and their standard deviations to correct the bias of the simulated temperatures. We did not use daily averaged temperatures to determine the risk of cool summer damage. Instead, we used the cooling degree calculated from the average daily temperature over a period of time(CDAT). We also used the standardized yield calculated from temperatures during the month preceding beading. An examination of the reproducibility of cooling damage occurring under the current climate was based on bias-corrected data which revealed that although the simulated risk of cool summer damage slightly underestimated both the CDAT and the standardized yield, the areal distributions of risk were similar to those in years of cool summer damage. We assumed that the heading stage occurred 15.6 days earlier than current climate because of the impact of temperature increase under the future climate and therefore calculated the CDAT and standardized yield by advancing the critical period by half a month. During the second- and third-coolest summers under the future climate scenario, the risk of cool summer damage decreased in the southern Tohoku region facing the Pacific Ocean and inAomori Prefecture on the Japan Sea side, but the risk of cool summer damage was almost the same as during the observed cool summer of 1980. In summary, our results revealed that under a future climate, simulated by the MRI AGCM, the risk of cool summer damage will persist in the Tohoku region; risk management for cool summer damage will therefore be essential, even though global temperatures rise

インドネシアジャワ島南央部における高地の天水農業の収量とグローバル指数との関係について

Although there has been a high interest to investigate the relationship between climate and crop yields in Indonesia, little evidence is available for crops in highland of the country. This study evaluates the relationships between global climate indices (Southern Oscillation Index, SOI; sea surface temperature, SST) and rain-fed crop yields in Gunungkidul district, highland of South-Central Java. Principal Component Analysis (PCA) approach was used to summarize the averaged SSTs during planting season for the El Nino monitoring regions: IOBW (Indian Ocean Basin-Wide), Nino.West and Niiio.3. Crops yield of each sub-district of the area was detrended using a 5-year moving average to enhance reliability of the data. For some sub-districts, the first principal component of SSTs was negatively correlated to crop yield residuals of corn and soybean while SOI was positively correlated to that of corn and dryland paddy.インドネシアにおいては気候と農作物収量との関係に高い関心が寄せられているが，高地農業に関しては進展が少ない状況である。本研究では，南方振動指数（SOI）および海水面温度（SST）のグローバル指数とジャワ島南央部に位置するグヌンキドウール地区における天水農作物収量との関係を分析した。３つの地域（IOBW, Niňo.ＷestおよびNiňo.3）のＳＳＴに対して主成分分折（PCA）を適用し，その代表となる主成分を抽出した。各地域の作物収量データの信頼性を向上させるために，元の収量データとその５年移動平均値から残差を計算し，正規化した。いくつかの地域では，SSTの第１主成分とトウモロコシ・ダイズの残差との間に負の相関を示し，またSOIはトウモロコシ・陸稲の残差との間に正の相関を示すことが明らかとなった

Indigenous Climate Information and Modern Meteorological Records in Sinazongwe District, Southern Province, Zambia

In 2007, we conducted field research in Sinazongwe District in Southern Province, Zambia, focusing on collecting indigenous information concerning the local climate, which was often embodied in proverbs involving weather forecasts. The indigenous information was compared with recently collected meteorological records and a relationship between popular folk knowledge, local climate, and global climate factors such as ENSO (El Nino and the Southern Oscillation) was suggested. Proverbs related to agriculture and climate were categorized into four types of indicators used to forecast rain: the emergence of butterflies; tree characteristics (producing shoots, flowering, and dropping water); wind direction, wind speed, and temperature; and wind sound. The first two types are based on sea sonal changes in life forms, and the latter two use wind variations produced by synoptic pattern changes