Wally Was Right: Predictive Ability of the North Atlantic “Conveyor Belt” Hypothesis for Abrupt Climate Change

Figure 1: Three-dimensional models constructed from computed tomography scans of an older juvenile of Terebratulina unguicula (CAS183808; locality info: California, Cordell Bank National Marine Sanctu...

Figure 2: Consensus cladogram (left), illustrating a hypothesis of phylogenetic relationships among named orders of brachiopods; elongated green ellipses around terminal circles denote eight named bra...

Figure 3: Hypotheses of phylogenetic relationship among Spiralia. Red dots indicate nodes with poor or conflicting support, and names that have been associated with those clades are in red; blue recta...

Figure 4: Three hypotheses of relationship among extant brachiopods and phoronids. (a) Parsimony analysis of 112 morphological and embryological characters distributed among exemplar taxa from each ex...

Figure 5: Three-dimensional geometry of the base of the two brachiopod lophophore arms (tentacles/filaments absent). Black dots indicate the posterior position of the mouth between the two arms. Arrow...

Figure 6: Articulated brachiopod dorsal valve interiors illustrating mineralized lophophore supports tallied in Figure 7. (a) Brachiophores: paired projections visible just below strophic hinge line, ...

Figure 7: (a) Histogram of the number of genera per Phanerozoic time period possessing one of five different types of mineralized lophophore supports or no mineralized support at all, counted (S.J. Ca...

Figure 8: Generic diversity per geological stage in the Phanerozoic Eon, color-coded by ordinal affiliation. Adapted from Curry & Brunton (2007), with permission from G. Curry.

Figure 1: The Wilson Cycle of the opening and the closing of the ocean basins. Plate tectonic analysis, which requires rigid-body rotations, is not possible for times before the age of the oldest pres...

Figure 2: Circum–West African craton suture zone. An early application of Wilson Cycle interpretation to Precambrian geology by Burke and Whiteman in 1970. An old craton was recognized in West Africa,...

Figure 3: The Great Arc of the Caribbean. A change in emphasis in Wilson Cycle interpretations of regional geology in recent decades has been that island arcs and ribbon continents that have collided ...

Figure 4: Shear wave velocity map at the core-mantle boundary (CMB) (from Becker & Boschi 2002). Thick lines are the plume generation zones (PGZs) that lie on 1% slow shear wave velocity contours on t...

Figure 5: Equatorial cross section of Earth showing mantle circulation dominated by sinking mantle, which consists of lithospheric slabs and slab debris (shown between blue arrows), and rising mantle ...

Figure 1: The CO2 system of the atmosphere, the ocean, and its sediments. The equilibrium between CO2 gas in the atmosphere and dissolved aqueous CO2 in seawater is set by K0, the Henry's law constant...

Figure 2: Difference in partial pressure of CO2 between the surface ocean and the atmosphere. Atmospheric reconstructions can be obtained from the marine realm because CO2 cycles rapidly between the s...

Figure 3: Relationships between key components of the CO2 system as a function of the master variables, alkalinity and dissolved inorganic carbon (DIC). CO2 contours show the atmospheric CO2 concentra...

Figure 4: Updated CO2 reconstructions from alkenone δ13C. (a) Benthic δ18O from Westerhold et al. (2020); individual data points in gray crosses with loess smooth in dark gray line. (b) Carbon isotope...

Figure 5: Boron isotope-derived estimates of pH and CO2. (a) Benthic δ18O from Westerhold et al. (2020). (b) δ11B on planktic foraminifera corrected for vital effects to give δ11B of borate (colored s...

Figure 6: Cenozoic CO2 and global climate. (a) Surface temperature estimated from the benthic δ18O stack of Westerhold et al. (2020), using the algorithm of Hansen et al. (2013). (b) Sea level estimat...

Figure 7: Relationship between CO2 and climate over the Cenozoic. Atmospheric CO2 is as plotted in Figure 6, binned into 0.01 Myr time windows and shown on a log(2) scale to display CO2 doublings. Sym...

Figure 8: Paleo-CO2 context for future CO2 change scenarios. Note the breaks in the age axis to allow different timescales to be compared. CO2 scenarios associated with shared socioeconomic pathways (...

Figure 1: Exponential increases in atmospheric CO2 and CH4 concentrations since 1850 (adapted from Raynaud et al. 2002).

Figure 2: The spread of agriculture from several centers of origin during the past 10,000 years (after Bellwood 2004, Fuller 2010). Numbers (white font) mark the time in thousands of years of initial ...

Figure 3: The radiocarbon-dated time of arrival of the fertile crescent crop package in southwest Asia and Europe (after Zohary & Hopf 1993).

Figure 4: The radiocarbon-dated spread of irrigated rice agriculture across southern Asia (adapted from Fuller et al. 2011).

Figure 5: Land-use records (incomplete and fully reliable) of deforestation and reforestation.

Figure 6: Estimate of global human population and farming technologies during the Holocene (after McEvedy & Jones 1978).

Figure 7: (a) Per-capita decrease of cultivated land in China (after Buck 1937, Chao 1986) (the anomalously low cultivation value in the year 976 followed shortly after a war that left much of the lan...

Figure 8: Land-use simulations of clearance of natural vegetation as of 1800 based on (top) historical records of large early per-capita clearance (KK10 1800) and (bottom) the assumption of small cons...

Figure 9: Estimated area of rice farming from 5,000 to 1,000 years ago (after Fuller et al. 2011).

Figure 10: Two schematic plots of the relative amount of forest clearance during industrial and preindustrial times. Note scale changes at 1,000 years ago.

Figure 11: Preindustrial Holocene CH4 and CO2 concentrations (red circles) compared with average (dark blue circles) and standard deviation (light blue shading) during previous interglaciations (based...

Figure 12: (a) Estimated effect of CH4 emissions from irrigated rice agriculture on atmospheric concentrations compared with (b) CH4 values measured in Dome C ice core prior to the industrial era (EPI...

Figure 13: Radiocarbon-dated first appearances of domesticated livestock in Asia and Africa (after Fuller et al. 2011).

Figure 14: Model simulation of cumulative release of carbon (KK10 carbon emissions curve) caused by preindustrial land clearance from 7,000 years ago until the year 1850 compared with estimated popula...

Figure 15: Holocene trend in atmospheric CO2 concentration compared with two differing estimates of past population levels: CO2 concentrations from EPICA Community Members (2004) (red circles); popula...

Figure 16: Two estimates of carbon transfers among major reservoirs that account for a net release of ∼50 billion tons of carbon to the atmosphere in the past 7,000 years: (a) small peat burial and an...

Figure 17: Direct anthropogenic emissions of CO2 and CH4 warm the ocean, which sends additional CO2 to the atmosphere as a feedback.

Figure 18: Two schematic plots of increases in atmospheric CO2 concentrations caused by anthropogenic carbon emissions during industrial and preindustrial times. Note scale changes at 1,000 years ago.

Figure 19: Change in global average temperature for different concentrations of atmospheric CO2 (courtesy of J.E. Kutzbach, work in progress).

Figure 20: Model simulation of months of permanent snow cover if greenhouse-gas concentrations today were as low as those predicted by the early-anthropogenic hypothesis (adapted from Vavrus et al. 20...

Figure 21: Two schematic plots of the relative size of anthropogenically driven temperature increases during industrial and preindustrial times. Note scale changes at 1,000 years ago.