Statistical characterisation of winter precipitation in the Abruzzo region (Italy) in relation to the North Atlantic Oscillation (NAO)
This paper analyses the relationship between the North Atlantic Oscillation (NAO) and winter precipitation at 75 stations in the Abruzzo region (Central Italy) during the period 1951-2009. The analysis was carried out for individual months (December, January, February, March) as well as for 3-month...
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Online Access: | http://hdl.handle.net/11391/1377007 https://doi.org/10.1016/j.atmosres.2016.03.028 http://www.sciencedirect.com/science/article/pii/S0169809516300849 |
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ftuniperugiairis:oai:research.unipg.it:11391/1377007 2024-04-14T08:15:38+00:00 Statistical characterisation of winter precipitation in the Abruzzo region (Italy) in relation to the North Atlantic Oscillation (NAO) VERGNI, LORENZO Di Lena, Bruno Chiaudani, Alessandro Vergni, Lorenzo Di Lena, Bruno Chiaudani, Alessandro 2016 STAMPA http://hdl.handle.net/11391/1377007 https://doi.org/10.1016/j.atmosres.2016.03.028 http://www.sciencedirect.com/science/article/pii/S0169809516300849 eng eng info:eu-repo/semantics/altIdentifier/wos/WOS:000378360700026 volume:178-179 firstpage:279 lastpage:290 numberofpages:12 journal:ATMOSPHERIC RESEARCH http://hdl.handle.net/11391/1377007 doi:10.1016/j.atmosres.2016.03.028 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-84963701907 http://www.sciencedirect.com/science/article/pii/S0169809516300849 Drought event L-moment Probability distribution Spatial variability info:eu-repo/semantics/article 2016 ftuniperugiairis https://doi.org/10.1016/j.atmosres.2016.03.028 2024-03-21T15:51:35Z This paper analyses the relationship between the North Atlantic Oscillation (NAO) and winter precipitation at 75 stations in the Abruzzo region (Central Italy) during the period 1951-2009. The analysis was carried out for individual months (December, January, February, March) as well as for 3-month accumulation periods, December to February (DJF) and January to March (JFM). A composite analysis, based on the positive and negative values of the North Atlantic Oscillation Index (NAOI) was used to compare the characteristics of precipitation associated with NAOI positive (NAO+) and negative (NAO-) conditions. Firstly, the NAO+ and NAO- precipitation subsets were compared by using the Brown-Forsythe and Mann-Whitney tests to assess the presence of significant differences in the variance and mean, respectively. Then the L-moment ratio diagrams were used to identify, for each period and NAO phase, the best-fitting two-parameter distribution. The NAO+ and NAO- conditions were also compared on the basis of the first (D1) and ninth (D9) precipitation deciles. The results show that the NAO mainly affects the mean precipitation amounts that are in most cases lower (higher) during the NAO+ (NAO-) phase, particularly for JFM. This influence is characterised by a relevant spatial variability that can be attributed to local factors (orography and distance from the sea). No significant differences were found in the precipitation variance, but this means that NAO+ precipitation, due to lower mean values, is relatively more variable than NAO- precipitation. The L-moment ratio diagrams reveal that the Weibull distribution always provides the best overall fitting for NAO- conditions (with the exception of DJF for which the log-normal is the best). For NAO+ conditions the best-fitting distributions become the generalized Pareto (January and February), the Weibull (DJF) and the Gamma (JFM), while no change in the distribution type is observed in December and March. In most cases, both D1 and D9 are lower during NAO+ phases. However, ... Article in Journal/Newspaper North Atlantic North Atlantic oscillation IRIS Università degli Studi di Perugia Atmospheric Research 178-179 279 290 |
institution |
Open Polar |
collection |
IRIS Università degli Studi di Perugia |
op_collection_id |
ftuniperugiairis |
language |
English |
topic |
Drought event L-moment Probability distribution Spatial variability |
spellingShingle |
Drought event L-moment Probability distribution Spatial variability VERGNI, LORENZO Di Lena, Bruno Chiaudani, Alessandro Statistical characterisation of winter precipitation in the Abruzzo region (Italy) in relation to the North Atlantic Oscillation (NAO) |
topic_facet |
Drought event L-moment Probability distribution Spatial variability |
description |
This paper analyses the relationship between the North Atlantic Oscillation (NAO) and winter precipitation at 75 stations in the Abruzzo region (Central Italy) during the period 1951-2009. The analysis was carried out for individual months (December, January, February, March) as well as for 3-month accumulation periods, December to February (DJF) and January to March (JFM). A composite analysis, based on the positive and negative values of the North Atlantic Oscillation Index (NAOI) was used to compare the characteristics of precipitation associated with NAOI positive (NAO+) and negative (NAO-) conditions. Firstly, the NAO+ and NAO- precipitation subsets were compared by using the Brown-Forsythe and Mann-Whitney tests to assess the presence of significant differences in the variance and mean, respectively. Then the L-moment ratio diagrams were used to identify, for each period and NAO phase, the best-fitting two-parameter distribution. The NAO+ and NAO- conditions were also compared on the basis of the first (D1) and ninth (D9) precipitation deciles. The results show that the NAO mainly affects the mean precipitation amounts that are in most cases lower (higher) during the NAO+ (NAO-) phase, particularly for JFM. This influence is characterised by a relevant spatial variability that can be attributed to local factors (orography and distance from the sea). No significant differences were found in the precipitation variance, but this means that NAO+ precipitation, due to lower mean values, is relatively more variable than NAO- precipitation. The L-moment ratio diagrams reveal that the Weibull distribution always provides the best overall fitting for NAO- conditions (with the exception of DJF for which the log-normal is the best). For NAO+ conditions the best-fitting distributions become the generalized Pareto (January and February), the Weibull (DJF) and the Gamma (JFM), while no change in the distribution type is observed in December and March. In most cases, both D1 and D9 are lower during NAO+ phases. However, ... |
author2 |
Vergni, Lorenzo Di Lena, Bruno Chiaudani, Alessandro |
format |
Article in Journal/Newspaper |
author |
VERGNI, LORENZO Di Lena, Bruno Chiaudani, Alessandro |
author_facet |
VERGNI, LORENZO Di Lena, Bruno Chiaudani, Alessandro |
author_sort |
VERGNI, LORENZO |
title |
Statistical characterisation of winter precipitation in the Abruzzo region (Italy) in relation to the North Atlantic Oscillation (NAO) |
title_short |
Statistical characterisation of winter precipitation in the Abruzzo region (Italy) in relation to the North Atlantic Oscillation (NAO) |
title_full |
Statistical characterisation of winter precipitation in the Abruzzo region (Italy) in relation to the North Atlantic Oscillation (NAO) |
title_fullStr |
Statistical characterisation of winter precipitation in the Abruzzo region (Italy) in relation to the North Atlantic Oscillation (NAO) |
title_full_unstemmed |
Statistical characterisation of winter precipitation in the Abruzzo region (Italy) in relation to the North Atlantic Oscillation (NAO) |
title_sort |
statistical characterisation of winter precipitation in the abruzzo region (italy) in relation to the north atlantic oscillation (nao) |
publishDate |
2016 |
url |
http://hdl.handle.net/11391/1377007 https://doi.org/10.1016/j.atmosres.2016.03.028 http://www.sciencedirect.com/science/article/pii/S0169809516300849 |
genre |
North Atlantic North Atlantic oscillation |
genre_facet |
North Atlantic North Atlantic oscillation |
op_relation |
info:eu-repo/semantics/altIdentifier/wos/WOS:000378360700026 volume:178-179 firstpage:279 lastpage:290 numberofpages:12 journal:ATMOSPHERIC RESEARCH http://hdl.handle.net/11391/1377007 doi:10.1016/j.atmosres.2016.03.028 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-84963701907 http://www.sciencedirect.com/science/article/pii/S0169809516300849 |
op_doi |
https://doi.org/10.1016/j.atmosres.2016.03.028 |
container_title |
Atmospheric Research |
container_volume |
178-179 |
container_start_page |
279 |
op_container_end_page |
290 |
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1796314029145194496 |