A1 Vertaisarvioitu alkuperäisartikkeli tieteellisessä lehdessä
Extreme Floods in Small Mediterranean Catchments: Long-Term Response to Climate Variability and Change
Tekijät: Benito G, Sanchez-Moya Y, Medialdea A, Barriendos M, Calle M, Rico M, Sopena A, Machado MJ
Kustantaja: MDPI
Julkaisuvuosi: 2020
Journal: Water
Tietokannassa oleva lehden nimi: WATER
Lehden akronyymi: WATER-SUI
Artikkelin numero: ARTN 1008
Vuosikerta: 12
Numero: 4
Sivujen määrä: 23
eISSN: 2073-4441
DOI: https://doi.org/10.3390/w12041008
Rinnakkaistallenteen osoite: https://research.utu.fi/converis/portal/Publication/50333796
Climate change implies changes in the frequency and magnitude of flood events. The influence of climate variability on flooding was evaluated by an analysis of sedimentary (palaeofloods) and documentary archives. A 500-year palaeoflood record at Montilea River (657 km(2) in catchment area), eastern Spain, revealed up to 31 palaeofloods with a range of discharges of 20-950 m(3) s(-1), and with at least five floods exceeding 740-950 m(3) s(-1). This information contrasts with the available gauged flood registers (since year 1971) with an annual maximum daily discharge of 129 m(3) s(-1). Our palaeoflood dataset indicates flood cluster episodes at (1) 1570-1620, (2) 1775-1795, (3) 1850-1890, and (4) 1920-1969. Flood rich periods 1 and 3 corresponded to cooler than usual (about 0.3 degrees C and 0.2 degrees C) climate oscillations, whereas 2 and 4 were characterised by higher inter-annual climatic variability (floods and droughts). This high inter-annual rainfall variability increased over the last 150 years, leading to a reduction of annual maximum flow. Flood quantiles (>50 years) calculated from palaeoflood+gauged data showed 30%-40% higher peak discharges than those using only instrumental records, whereas when increasing the catchment area (1500 km(2)) the discharge estimation variance decreased to-15%. The results reflect the higher sensitivity of small catchments to changes on flood magnitude and frequency due to climate variability whereas a larger catchment buffers the response due to the limited extent of convective storms. Our findings show that extended flood records provide robust knowledge about hazardous flooding that can assist in the prioritization of low-regret actions for flood-risk adaptation to climate change.
Ladattava julkaisu This is an electronic reprint of the original article. |  |
