Atmospheric forcing over Holocene productivity in the Alboran Sea (W Mediterranean) from coccolithophores and Mg/Ca-estimated SST records (стр. 6 )

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Table 1. Age model for core HER-GC-T1. aPoznan Radiocarbon Laboratory. bWoods Hole Oceanographic Institution.

Radiocarbon (Sample/Laboratory code)	Foram Type	Depth (cm)	Radiocarbon Age (yr BP)	Calendar Age (yr cal BP)
SEC1_2/ Poz-53233a	G. inflata	2	440 ± 25	74.5±74.5
SEC1_21/OS-87586b	G. inflata	21	1810 ± 25	1386.5±102
SEC1_63/ Poz-53234a	G. inflata	63	4175 ± 35	4276±143
SEC2_17/ Poz-53235a	G. inflata	107	6100 ± 40	6543.5±134
SEC2_54/OS-87587b	G. inflata+ N. pachyderma	144	7350 ± 35	7827.5±113
SEC3_12/ Poz-53236a	N. pachyderma	202	10400 ± 60	11496±261

Figure 1. a) Map of the annual mean SST (єC) in the Western Mediterranean Sea. b) Study area and HER-GC-T1 core location in the Alboran Sea. c) Gulf of Lions area where the WMDW formation occurs. Black arrows trace general superficial circulation. Grey arrows trace general deep circulation. NASW: North Atlantic Surface Water, entering the Alboran Sea as the Atlantic Jet: AJ. MAW: Modified Atlantic Water. WMDW: Western Mediterranean Deep Water. MOW: Mediterranean Outflowing Water. WAG: Western Anticyclonic Gyre. EAG: Eastern Anticyclonic Gyre.

Figure 2. Age control points are marked by a black dot and associated error bars. The solid line that joins them is the age given in ka cal. BP. SR stands for sedimentation rate, given in cm*ka-1.

Figure 3. Mg/Ca-estimed SST (°C) from core HER-GC-T1. Nannofossil Accumulation Rate (NAR) (coccoliths*cm-2*ky-1) (black lines) and percentage abundance (%) (dashed line) of the coccolithophore assemblage. N ratio (small placoliths/(small placoliths+F. profunda). The grey bar indicates the 7.7 ka cal. BP event. Red stars stand for age control points (yr cal. BP) (Table 1).

Figure 4 a) Insolation curve (June, 36° N) (Laskar, 1990). b) Mg/Ca-estimated SST (°C). c) -estimated SST (°C). d) δ18O record (‰) (Note that vertical axis is reversed).

Figure 5. Paleorecords from core HER-GC-T1 compared to other environmental paleorecords. a) UP 10 record from core MD95-2343 north of Minorca (Frigola et al., 2007). Black stars stand for age control points (ka cal. BP). b) Alcohol index from core HER-GC-T1 c) N ratio. d) NAR of F. profunda. e) Relative abundance of reworked nannoliths. f) Pollen grains from core MD95-2043 in the Alboran Sea for all temperate and Mediterranean forest taxa (Fletcher et al., 2012). Age control points are marked by brown stars (Cacho et al., 1999). g) Mg/Ca-estimated SST. Occurrence of Minorca abrupt events (M events) are represented by bars.

Figure 6. a) Inferred NAO circulation pattern (Olsen et al., 2012). b) Comparison of PCA3 (Olsen et al., 2012) and UP10 fraction (reversed vertical axis) from core MD95-2343 north of Minorca (Frigola et al., 2007). c) Comparison of PCA3 with reworked nannoliths (reversed vertical axis) from HER-GC-T1 in the Alboran Sea. d) Comparison of PCA3 with Mg/Ca-estimated SST (reversed vertical axis) from HER-GC-T1 in the Alboran Sea. Pale brown bars represent the occurrence of Minorca abrupt events M5 to M0 (Frigola et al., 2007).

Figure 7. WMDW: Western Mediterranean Deep Water. LIW: Levantine Intermediate Water. DW: Deep waters (WMDW+LIW). MAW: Mediterranean-Atlantic water. AJ: Atlantic Jet. a) Scenario [1]: Persistent lower NAO index. Weaker westerlies trigger a slackening of the WMDW formation. This along with lesser and warmer AJ influx promotes deepening of the nutricline, which lead to long-term stratification events). b) Scenario [2]: dominant higher NAO index. Stronger westerlies enable a reinforcement of the WMDW formation. This along with major and colder AJ entering the Alboran Sea, lead to shoaling of the nutricline and a major vertical mixing. Accordingly, upwelling events occurs.