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Atlantic hurricane activity during the last millennium.

Burn MJ, Palmer SE - Sci Rep (2015)

Bottom Line: Hurricanes are a persistent socio-economic hazard for countries situated in and around the Main Development Region (MDR) of Atlantic tropical cyclones.However, the attribution of hurricane activity to specific forcing factors is hampered by the short observational record of Atlantic storms.Here, we present the Extended Hurricane Activity (EHA) index, the first empirical reconstruction of Atlantic tropical cyclone activity for the last millennium, derived from a high-resolution lake sediment geochemical record from Jamaica.

View Article: PubMed Central - PubMed

Affiliation: Department of Geography and Geology, The University of the West Indies, Mona Campus, Kingston 7, Jamaica, W.I.

ABSTRACT
Hurricanes are a persistent socio-economic hazard for countries situated in and around the Main Development Region (MDR) of Atlantic tropical cyclones. Climate-model simulations have attributed their interdecadal variability to changes in solar and volcanic activity, Saharan dust flux, anthropogenic greenhouse gas and aerosol emissions and heat transport within the global ocean conveyor belt. However, the attribution of hurricane activity to specific forcing factors is hampered by the short observational record of Atlantic storms. Here, we present the Extended Hurricane Activity (EHA) index, the first empirical reconstruction of Atlantic tropical cyclone activity for the last millennium, derived from a high-resolution lake sediment geochemical record from Jamaica. The EHA correlates significantly with decadal changes in tropical Atlantic sea surface temperatures (SSTs; r = 0.68; 1854-2008), the Accumulated Cyclone Energy index (ACE; r = 0.90; 1851-2010), and two annually-resolved coral-based SST reconstructions (1773-2008) from within the MDR. Our results corroborate evidence for the increasing trend of hurricane activity during the Industrial Era; however, we show that contemporary activity has not exceeded the range of natural climate variability exhibited during the last millennium.

No MeSH data available.


Related in: MedlinePlus

Time-series analyses of the Extended Hurricane Activity (EHA) index and comparison with natural external forcing (a) Changes in volcanic forcing52 (black line, upper panel) and (b) Total Solar Irradiance (TSI)5051 (yellow and black). (c) PC3 sequence of lake-level change at Grape Tree Pond, Jamaica27 (grey) and the Extended Hurricane Activity (EHA) index (blue) calculated for the geographic region defined by the grid box 15–25°N, 70–80°W. The black line represents the section of the PC3 series anchored to the annually-resolved coral-based SST reconstruction from the Yucatan Peninsula30 (d) Annual basin-wide tropical cyclone counts from a coupled ocean-atmosphere climate model simulation35 (light blue), and from statistical model reconstructions driven by estimates of landfalling hurricane strikes from overwash sediment records36 (pink). (e) Morlet wavelet analysis applied to the PC3 sequence from Grape Tree Pond, Jamaica. Colours represent the signal strength, which is the squared correlation strength with the scaled morlet wavelet. The 95% confidence level is plotted as a contour and the cone of influence identifies the region of the wavelet spectrum in which boundary effects are present. (f) Bandpass filters applied to the PC3 sequence centred on interannual (5–8 years; grey) and interdecadal timescales (54–80 years; green). Intervals associated with the five grand solar minima are shaded in grey and those of the Medieval Climate Anomaly (MCA) and Little Ice Age (LIA) are represented in open boxes with dashed lines extended to the top of the figure.
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f4: Time-series analyses of the Extended Hurricane Activity (EHA) index and comparison with natural external forcing (a) Changes in volcanic forcing52 (black line, upper panel) and (b) Total Solar Irradiance (TSI)5051 (yellow and black). (c) PC3 sequence of lake-level change at Grape Tree Pond, Jamaica27 (grey) and the Extended Hurricane Activity (EHA) index (blue) calculated for the geographic region defined by the grid box 15–25°N, 70–80°W. The black line represents the section of the PC3 series anchored to the annually-resolved coral-based SST reconstruction from the Yucatan Peninsula30 (d) Annual basin-wide tropical cyclone counts from a coupled ocean-atmosphere climate model simulation35 (light blue), and from statistical model reconstructions driven by estimates of landfalling hurricane strikes from overwash sediment records36 (pink). (e) Morlet wavelet analysis applied to the PC3 sequence from Grape Tree Pond, Jamaica. Colours represent the signal strength, which is the squared correlation strength with the scaled morlet wavelet. The 95% confidence level is plotted as a contour and the cone of influence identifies the region of the wavelet spectrum in which boundary effects are present. (f) Bandpass filters applied to the PC3 sequence centred on interannual (5–8 years; grey) and interdecadal timescales (54–80 years; green). Intervals associated with the five grand solar minima are shaded in grey and those of the Medieval Climate Anomaly (MCA) and Little Ice Age (LIA) are represented in open boxes with dashed lines extended to the top of the figure.

Mentions: Our reconstruction of hurricane activity is derived from the third Principal Component (PC3) of mm-scale ITRAX μ-XRF core scans of a ~1200-year long sediment record of lake-level change from Grape Tree Pond in southern Jamaica27 (Figs 1,2a,3d and 4c). The pond is a freshwater-fed and anoxic mangrove lagoon, which is sensitive to precipitation variability on multiple timescales. High rates of sediment accumulation (~2.5 mm−yr) combined with low levels of bioturbation result in sedimentation rates sufficient to capture geochemical changes at an annual resolution. We improve the original 14C-based age model for the site by anchoring the PC3 record to the annually resolved coral-based SST reconstruction from the eastern Yucatan Peninsula30 for the period 1775–2009 (Fig. 1; see methods). Of the first three principal components of the geochemical data, PC1 explains 47.6% of the variance within the dataset and represents a gradient of sediment deposition from organic sediments to a combination of inorganic authigenic and detrital elements, the latter interpreted to reflect the aerial deposition of Saharan dust27. PC2 explains 11.9% of the variance and represents a salinity gradient. PC3 explains 8.9% of the variance and represents a gradient of redox conditions at the sediment-water interface of the lagoon and exhibits a positive relationship with lake level change27.


Atlantic hurricane activity during the last millennium.

Burn MJ, Palmer SE - Sci Rep (2015)

Time-series analyses of the Extended Hurricane Activity (EHA) index and comparison with natural external forcing (a) Changes in volcanic forcing52 (black line, upper panel) and (b) Total Solar Irradiance (TSI)5051 (yellow and black). (c) PC3 sequence of lake-level change at Grape Tree Pond, Jamaica27 (grey) and the Extended Hurricane Activity (EHA) index (blue) calculated for the geographic region defined by the grid box 15–25°N, 70–80°W. The black line represents the section of the PC3 series anchored to the annually-resolved coral-based SST reconstruction from the Yucatan Peninsula30 (d) Annual basin-wide tropical cyclone counts from a coupled ocean-atmosphere climate model simulation35 (light blue), and from statistical model reconstructions driven by estimates of landfalling hurricane strikes from overwash sediment records36 (pink). (e) Morlet wavelet analysis applied to the PC3 sequence from Grape Tree Pond, Jamaica. Colours represent the signal strength, which is the squared correlation strength with the scaled morlet wavelet. The 95% confidence level is plotted as a contour and the cone of influence identifies the region of the wavelet spectrum in which boundary effects are present. (f) Bandpass filters applied to the PC3 sequence centred on interannual (5–8 years; grey) and interdecadal timescales (54–80 years; green). Intervals associated with the five grand solar minima are shaded in grey and those of the Medieval Climate Anomaly (MCA) and Little Ice Age (LIA) are represented in open boxes with dashed lines extended to the top of the figure.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4525293&req=5

f4: Time-series analyses of the Extended Hurricane Activity (EHA) index and comparison with natural external forcing (a) Changes in volcanic forcing52 (black line, upper panel) and (b) Total Solar Irradiance (TSI)5051 (yellow and black). (c) PC3 sequence of lake-level change at Grape Tree Pond, Jamaica27 (grey) and the Extended Hurricane Activity (EHA) index (blue) calculated for the geographic region defined by the grid box 15–25°N, 70–80°W. The black line represents the section of the PC3 series anchored to the annually-resolved coral-based SST reconstruction from the Yucatan Peninsula30 (d) Annual basin-wide tropical cyclone counts from a coupled ocean-atmosphere climate model simulation35 (light blue), and from statistical model reconstructions driven by estimates of landfalling hurricane strikes from overwash sediment records36 (pink). (e) Morlet wavelet analysis applied to the PC3 sequence from Grape Tree Pond, Jamaica. Colours represent the signal strength, which is the squared correlation strength with the scaled morlet wavelet. The 95% confidence level is plotted as a contour and the cone of influence identifies the region of the wavelet spectrum in which boundary effects are present. (f) Bandpass filters applied to the PC3 sequence centred on interannual (5–8 years; grey) and interdecadal timescales (54–80 years; green). Intervals associated with the five grand solar minima are shaded in grey and those of the Medieval Climate Anomaly (MCA) and Little Ice Age (LIA) are represented in open boxes with dashed lines extended to the top of the figure.
Mentions: Our reconstruction of hurricane activity is derived from the third Principal Component (PC3) of mm-scale ITRAX μ-XRF core scans of a ~1200-year long sediment record of lake-level change from Grape Tree Pond in southern Jamaica27 (Figs 1,2a,3d and 4c). The pond is a freshwater-fed and anoxic mangrove lagoon, which is sensitive to precipitation variability on multiple timescales. High rates of sediment accumulation (~2.5 mm−yr) combined with low levels of bioturbation result in sedimentation rates sufficient to capture geochemical changes at an annual resolution. We improve the original 14C-based age model for the site by anchoring the PC3 record to the annually resolved coral-based SST reconstruction from the eastern Yucatan Peninsula30 for the period 1775–2009 (Fig. 1; see methods). Of the first three principal components of the geochemical data, PC1 explains 47.6% of the variance within the dataset and represents a gradient of sediment deposition from organic sediments to a combination of inorganic authigenic and detrital elements, the latter interpreted to reflect the aerial deposition of Saharan dust27. PC2 explains 11.9% of the variance and represents a salinity gradient. PC3 explains 8.9% of the variance and represents a gradient of redox conditions at the sediment-water interface of the lagoon and exhibits a positive relationship with lake level change27.

Bottom Line: Hurricanes are a persistent socio-economic hazard for countries situated in and around the Main Development Region (MDR) of Atlantic tropical cyclones.However, the attribution of hurricane activity to specific forcing factors is hampered by the short observational record of Atlantic storms.Here, we present the Extended Hurricane Activity (EHA) index, the first empirical reconstruction of Atlantic tropical cyclone activity for the last millennium, derived from a high-resolution lake sediment geochemical record from Jamaica.

View Article: PubMed Central - PubMed

Affiliation: Department of Geography and Geology, The University of the West Indies, Mona Campus, Kingston 7, Jamaica, W.I.

ABSTRACT
Hurricanes are a persistent socio-economic hazard for countries situated in and around the Main Development Region (MDR) of Atlantic tropical cyclones. Climate-model simulations have attributed their interdecadal variability to changes in solar and volcanic activity, Saharan dust flux, anthropogenic greenhouse gas and aerosol emissions and heat transport within the global ocean conveyor belt. However, the attribution of hurricane activity to specific forcing factors is hampered by the short observational record of Atlantic storms. Here, we present the Extended Hurricane Activity (EHA) index, the first empirical reconstruction of Atlantic tropical cyclone activity for the last millennium, derived from a high-resolution lake sediment geochemical record from Jamaica. The EHA correlates significantly with decadal changes in tropical Atlantic sea surface temperatures (SSTs; r = 0.68; 1854-2008), the Accumulated Cyclone Energy index (ACE; r = 0.90; 1851-2010), and two annually-resolved coral-based SST reconstructions (1773-2008) from within the MDR. Our results corroborate evidence for the increasing trend of hurricane activity during the Industrial Era; however, we show that contemporary activity has not exceeded the range of natural climate variability exhibited during the last millennium.

No MeSH data available.


Related in: MedlinePlus