Relationship between west African rainfall and the survival of central European Sand Martins Riparia riparia

Ibis ◽  
1995 ◽  
Vol 137 (2) ◽  
pp. 162-168 ◽  
Author(s):  
TIBOR SZEP
2015 ◽  
Vol 18 ◽  
pp. 21-27
Author(s):  
Rüdiger Wittig

In spite of enormous climatic differences between Burkina Faso and Germany, 20 species belong to the spontaneous flora of both countries, i.e. 1% of the flora of Burkina Faso and 0.15 % of the German flora. All of them are either ruderal and segetal species (16) or water and reed plants (4). All of the 16 ruderals/segetals are therophytes. From a recent point of view, most of the 20 species can be classified as cosmopolitan, because they cover three and more floristic zones, and/or at least three climatic zones, and/or are represented in at least three continents. Although Burkina Faso has a semi-arid climate, none of the species can be called a sclero- or xerophyte. Therefore, in Burkina Faso, all are more or less bound to habitats at least temporarily flooded or to humid soils. In Germany, however, the concerned ruderals, with one exception, are indicators of medium dry or dry habitats.


Ibis ◽  
2008 ◽  
Vol 133 (3) ◽  
pp. 300-305 ◽  
Author(s):  
WILL PEACH ◽  
STEPHEN BAILLIE ◽  
LES UNDERHILL

Author(s):  
Christopher E. Ndehedehe ◽  
Muhammad Usman ◽  
Onuwa Okwuashi ◽  
Vagner G. Ferreira

2017 ◽  
Vol 30 (12) ◽  
pp. 4625-4632 ◽  
Author(s):  
D. Whittleston ◽  
S. E. Nicholson ◽  
A. Schlosser ◽  
D. Entekhabi

Changes in large-scale dynamics over West Africa—the strength and position of zonal jets—are a key interim step by which local and remote forcing is communicated into changes in rainfall. This study identifies a key mode of jet variability and demonstrates how it is strongly coupled with rainfall. The approach provides a quantitative framework to assess jet–rainfall coupling and a useful tool to investigate the concerning spread in CMIP5 rainfall projections over the West African Sahel. It is shown that many CMIP5 simulations fail to capture this coupling, indicating a fundamental limitation in their ability to predict future rainfall conditions. The results demonstrate that West African rainfall in the coming CMIP6 ensemble should be interpreted with caution; key atmospheric processes that deliver rainfall must be validated before conducting detailed analysis on rainfall.


2007 ◽  
Vol 22 (5) ◽  
pp. 937-949 ◽  
Author(s):  
Philip J. Klotzbach

Abstract Predictions of the remainder of the season’s Atlantic basin tropical cyclone activity from 1 August have been issued by Gray and his colleagues at the Tropical Meteorology Project at Colorado State University since 1984. The original 1 August prediction scheme utilized several predictors, including measures of the stratospheric quasi-biennial oscillation (QBO), West African rainfall, El Niño–Southern Oscillation, and the sea level pressure anomaly and upper-tropospheric zonal wind anomalies in the Caribbean basin. The recent failure of the West African rainfall and QBO relationships with Atlantic hurricanes has led to a general degradation of the original 1 August forecast scheme in recent years. It was decided to revise the scheme using only surface data. The development of the National Centers for Environmental Prediction–National Center for Atmospheric Research reanalysis has provided a vast wealth of globally gridded meteorological and oceanic data from 1948 to the present. In addition, other datasets have been extended back even further (to 1900), which allows for a large independent dataset. These longer-period datasets allow for an extended period of testing of the new statistical forecast scheme. A new prediction scheme has been developed on data from 1949 to 1989 and then tested on two independent datasets. One of these datasets is the 16-yr period from 1990 to 2005, and the other dataset is from 1900 to 1948. This allows for an investigation of the statistical significance over various time periods. The statistical scheme shows remarkable stability over an entire century. The combination of these four predictors explains between 45% and 60% of the variance in net tropical cyclone activity over the following separate time periods: 1900–48, 1949–89, 1949–2005, and 1900–2005. The forecast scheme also shows considerable skill as a potential predictor for giving the probabilities of United States landfall. Large differences in U.S. major hurricane landfall are also observed between forecasts that call for active seasons compared with those that call for inactive seasons.


2021 ◽  
Author(s):  
Magatte Sow ◽  
Françoise Guichard ◽  
Ross Dixon ◽  
Moussa Diakhate ◽  
Songnan Lou ◽  
...  

2021 ◽  
Author(s):  
Magatte Sow ◽  
Françoise Guichard ◽  
Ross Dixon ◽  
Moussa Diakhate ◽  
Songnan Lou ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document