Did China Approach Vanuatu to Build a Permanent Military Base?

China has approached Vanuatu about establishing a permanent military presence on the tiny Pacific island, Australia’s Fairfax Media reported on Tuesday, a plan that would likely stoke regional tensions.

The report, citing unnamed sources, said no formal proposal had yet been made, but preliminary talks have been held about locating a full military base on Vanuatu. It added that the prospect of a Chinese military outpost so close to Australia has been discussed at the highest levels in Canberra and Washington.

Australian Foreign Minister Julie Bishop on Tuesday said she had been assured by Vanuatu officials that there was no formal proposal from Beijing, but she stopped short of addressing whether there had been any unofficial talks.

“The government of Vanuatu has said there is no such proposal, but it is a fact that China is engaging in infrastructure investment activities around the world,” Bishop told Australian Broadcasting Corporation radio.

“I remain confident that Australia is Vanuatu’s strategic partner of choice,” she said.

A spokesman for Vanuatu Prime Minister Charlot Salwai did not immediately respond to emails requesting comment, telephone calls to the Vanuatu High Commission in Canberra were not answered, and the Chinese Embassy in Canberra did not comment.

The Fairfax Media report said the preliminary discussions involved an initial access agreement, under which Chinese naval ships would dock to be serviced, refueled and restocked, and that would eventually lead to a full military base.

Such a plan would mark an expansion of China’s military aspirations beyond its controversial activities in Asia, particularly the South China Sea, where it has been building artificial islands on reefs, some with ports and airstrips.

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Iron Fertilization Will NOT Work in the Pacific

Over the past half-million years, the equatorial Pacific Ocean has seen five spikes in the amount of iron-laden dust blown in from the continents. In theory, those bursts should have turbo-charged the growth of the ocean's carbon-capturing algae - algae need iron to grow - but a new study shows that the excess iron had little to no effect.

The results are important today, because as groups search for ways to combat climate change, some are exploring fertilizing the oceans with iron as a solution.

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paper link.

US Army Desperately Needs Future Vertical Lift for Pacific Theater

The deputy commander of US Pacific Command says the Army must field next-generation aircraft with greater range, speed and survivability than is achievable with today’s helicopter inventory.

Lt Gen Tony Crutchfield says the vast distances inherent in the Pacific theatre, as well as the proliferation of anti-aircraft weaponry, are challenging the current generation of army rotorcraft, namely the AH-6 Little Bird, UH-60 Black Hawk, AH-64 Apache and CH-47 Chinook, which were all adopted in the last century.

“I firmly believe the only way we will close the gap with the problems facing us today is with Future Vertical Lift (FVL),” he says, referring to the army-led acquisition programme that will introduce a new family of aircraft with roughly double the range and speed of today’s models.

“We must have Future Vertical Lift,” he continues, speaking at an Army Aviation Association of America conference in Atlanta, Georgia on 30 April. “It is the only way we will be successful in the PACOM environment with the distances. That range and that speed and that survivability are critical to army aviation to be effective in this fight.”

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Northeastern Pacific Ocean and the Bering Sea Hypoxic "Blob" Caused by Rapidly Rising Temperatures

A new study has found a link between abrupt ocean warming at the end of the last ice age and the sudden onset of low-oxygen, or hypoxic conditions that led to vast marine dead zones.

Results of the study, which was funded by the National Science Foundation, are being published this week in the journal Nature.

Large-scale warming events about 14,700 and again 11,500 years ago occurred rapidly and triggered loss of oxygen in the North Pacific, raising concern that low-oxygen areas will expand again as the ocean warms in the future. Anomalous warmth occurring recently in the Northeastern Pacific Ocean and the Bering Sea - dubbed "The Blob" - is of a scale similar to the events documented in the geologic record, the researchers say. If such warming is sustained, oxygen loss becomes more likely.

Although many scientists believe that a series of low-oxygen "dead zones" in the Pacific Ocean off Oregon and Washington during the last decade may be caused by ocean warming, evidence confirming that link has been sparse.

However, the new study found a clear connection between two prehistoric intervals of abrupt ocean warming that ended the last ice age with an increase in the flux of marine plankton sinking to the seafloor, ultimately leading to a sudden onset of low-oxygen conditions, or hypoxia.

"Our study reveals a strong link between ocean warming, loss of oxygen, and an ecological shift to favor diatom production," said lead author Summer Praetorius, who conducted the research as part of her doctoral studies at Oregon State University and is now a postdoctoral researcher at Carnegie Institution for Science.

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Subsurface Circulation Changed in Late Eocene Equatorial Pacific

Evidence for changes in subsurface circulation in the late Eocene equatorial Pacific from radiolarian-bound nitrogen isotope values

Authors:

Robinson et al

Abstract:

Microfossil bound organic matter represents an important archive of surface ocean environmental information. Sedimentary nitrogen (N) isotope reconstructions of surface nitrate consumption and nitrogen source changes are made using fossil diatom (autotrophs) and planktic foraminiferal (heterotrophs)-bound organic matter with success. However, because diatoms and planktic foraminifera are poorly preserved and sedimentary organic matter content is near zero during the late Eocene, our ability to examine nutrient dynamics across this important climate transition is limited. Here we present new data exploring the use of N isotope records from radiolarian tests. A comparison of surface ocean nitrate and core top bulk and radiolarian N isotope values (as δ15N) from the equatorial Pacific indicates that radiolarian-N records δ15N variability with fidelity but that a significant offset exists between bulk sedimentary and diatom δ15N values and those measured from radiolarians (~7.1± 1.1‰). A downcore profile of radiolarian δ15N values is compared to siliceous microfossil assemblage changes across the Eocene-Oligocene boundary. Average of radiolarian-bound δ15N values is 0.5 ± 2.0 ‰, which, when corrected using the offset derived from the modern surface samples, suggests that the mean nitrogen isotopic composition of the early Cenozoic eastern Pacific was not significantly different from today. The overall trend, of decreasing δ15N values with decreasing export productivity, is consistent with either a regional decline in pelagic denitrification or a large scale change in nutrient sources to the eastern equatorial Pacific (EEP), both linked to the cooling climate and changing intermediate water circulation. Decreasing/low δ15N values co-occur with high radiolarian species turnover at ~35.5 and 34 Ma, suggestive of a significant ecological change in the EEP, consistent with cooling and water mass distribution changes. The preliminary results suggest that radiolarian-bound organic nitrogen represents another promising archive and underscore the fact that the different microfossil fractions must be separated to ensure robust results.

Evidence of Albian/Cenomanian Cretaceous Environmental Pertubation From Peru

Record of Albian to early Cenomanian environmental perturbation in the eastern sub-equatorial Pacific

Authors:

Navarro-Ramirez et al

Abstract:

The present paper documents and discusses a new Albian–early Cenomanian carbon isotope (δ13Ccarb and δ13Corg) curve from the subequatorial Eastern Pacific in Peru. Chemostratigraphic evidences for the expression of the OAE1b set and for OAE1c and OAE1d are presented. This dataset is relevant inasmuch as previous work is strongly biased towards study sites in North America (Western Interior Basin), in Europe (Tethys) and the Pacific realm. A comparison of the carbon isotope stratigraphy obtained in Peru with published sections from the Central and Western Pacific, the Western Atlantic and Northern and Western Tethys reveals an overall good agreement supporting the global nature of the isotope patterns described here. The δ13C from Peru record is constrained by biostratigraphic evidence and 87Sr/86Sr isotope stratigraphy using well-preserved oyster shells. Furthermore, we document the development of a heterozoan epeiric-neritic mixed carbonate-siliciclastic ramp in the Western Platform of Peru and its corresponding sedimentary facies associations. This dataset was used to elucidate the complex interplay of climatic changes, nutrient supply, and platform drowning, leading to the following conclusions: (i) An upper Aptian–lower Albian major change from siliciclastic-dominated to carbonate sedimentation coincided with the impact of the Kilian Level. (ii) A lower Albian incipient platform drowning linked to the impact of the Paquier Level. (iii) A lower middle Albian major demise of neritic carbonate production that coincides with the Leenhardt Level, followed by middle Albian condensed sedimentation that reports prominent negative values in δ13Ccarb prior to the onset of OAE1c. (4) Finally, renewed carbonate ramp production during the upper Albian–lower Cenomanian. The data shown here represent the foundation for future work documenting the mid–Cretaceous of Peru and its implications for the palaeoceanography of the SE subequatorial Pacific.

Cambrian Radiation Linked to an Iapetus-Pacific Oceanic Connection?

Cambrian transgression and radiation linked to an Iapetus-Pacific oceanic connection?

Author:

Dalziel

Abstract:

The geologically abrupt appearance in the fossil record of almost all animal phyla is referred to as the Cambrian radiation or "explosion" of life on Earth. Also known as "Darwin's dilemma," because it seemingly posed a major problem for his theory of gradual evolution, it coincided with the initiation of the first of the two principal global marine transgressions of the Phanerozoic. Although now seen as more protracted, it is still one of the most striking and critical events in the history of the biosphere. Almost all paleogeographic reconstructions for the early Cambrian feature a previously isolated Laurentia, the core of ancestral North America. Yet geological evidence from five continents, integrated here for the first time, indicates that the present-day "southern cone" of Laurentia was still attached to the newly amalgamated supercontinent of Gondwanaland into Cambrian times. Laurentia was then isolated by the development of a major deep oceanic connection between the opening Iapetus Ocean basin and the already well-developed paleo-Pacific. As the marine transgression advanced, major changes in ocean chemistry occurred, upwelling generated phosphorite deposits, and the number of fossilized metazoan phyla "exploded" with morphologic disparity between Laurentia and Gondwanaland already established. The development of this deep oceanic gateway, and of an ocean floor–consuming and arc-generating subduction zone along virtually the entire margin of Gondwanaland shortly thereafter, need to be taken into account in consideration of the global environmental and biotic changes associated with the Neoproterozoic-Phanerozoic transition.

Evidence Walker Circulation is Weakening Over the Pacific Ocean

Equatorial Pacific coral geochemical records show recent weakening of the Walker Circulation

Authors:

Carilli et al

Abstract:

Equatorial Pacific ocean-atmosphere interactions affect climate globally, and a key component of the coupled system is the Walker Circulation, which is driven by sea surface temperature (SST) gradients across the equatorial Pacific. There is conflicting evidence as to whether the SST gradient and Walker Circulation have strengthened or weakened over the late 20th century. We present new records of SST and sea surface salinity (SSS) spanning 1959-2010 based on paired measurements of Sr/Ca and δ18O in a massive Porites coral from Butaritari atoll in the Gilbert Islands, Republic of Kiribati, in the central-western equatorial Pacific. The records show 2-7 year variability correlated with the El Niño-Southern Oscillation (ENSO) and corresponding shifts in the extent of the Indo-Pacific Warm Pool, and decadal-scale signals related to the Pacific Decadal Oscillation. In addition, the Butaritari coral records reveal a small but significant increase in SST (0.39 °C) from 1959 to 2010 with no accompanying change in SSS, a trend that persists even when ENSO variability is removed. In contrast, larger increases in SST and SSS are evident in coral records from the equatorial Pacific Line Islands, located east of Butaritari. Taken together, the equatorial Pacific coral records suggest an overall reduction in the east-west SST and SSS gradient over the last several decades, and a recent weakening of the Walker Circulation.

Neogene Marine Vertebrate Paleodiversity in Temperature Pacific South America

Rise and fall in diversity of Neogene marine vertebrates on the temperate Pacific coast of South America

Authors:

Villafaña et al

Abstract:

Even though Neogene outcrops along the temperate Pacific coast of South America harbor a rich marine vertebrate fossil record, no studies have examined the diversification patterns of these taxa. Here, we analyze diversification trends based on the stratigraphic ranges of 86 genera of marine vertebrates, including sharks, rays, chimaeras, marine mammals, and seabirds. The richness of genera shows a hump-shaped trend, with maximum values around the late Miocene, driven by a large pulse of origination during mid-Miocene and higher extinction rates during the Pliocene. Trends varied markedly among taxa and departed largely from expectations based on global diversification patterns. Moreover, these trends cannot be explained solely as a sampling artifact derived from sampling intensity (i.e., number of occurrences) or sedimentary rock availably (i.e., number of geologic maps). A large fraction of genera (42%) went globally extinct by the late Pliocene–Pleistocene, and the extinction was highly selective according to different ecological and life-history traits. An analysis using “randomForest” showed that taxonomic structure and the geographic midpoint of distribution could explain up to 83% of extinction of genera. The extinction was taxonomically clumped (i.e., disproportionally high in Cetacea and very low in Carcharhiniformes) and concentrated in the northern area of the temperate Pacific coast of South America. Our results suggest that the particular paleogeographic, paleoclimatic, and paleoceanographic events that took place during the Neogene along the temperate Pacific coast of South America had a significant effect on the structure of marine biodiversity.

Southwest Pacific Subtropics Response to Holocene/Pleistocene Quaternary Deglaciation

The Southwest Pacific subtropics responds to the last deglacial warming with changes in shallow water sources

Authors:

Schiraldi et al

Abstract:

This study examined sources of mixed layer and shallow subsurface waters in the subtropical Bay of Plenty, New Zealand across the last deglaciation (~30-5 ka). δ18O and δ13C from planktonic foraminifera Globgerinoides bulloides and Globorotalia inflata in four sediment cores were used to reconstruct surface mixed layer thickness, δ18O of seawater (δ18OSW) and differentiate between high and low latitude water provenance. During the last glaciation, depleted planktonic δ18OSW and enriched δ13C (-0.4-0.1‰) indicate surface waters had Southern Ocean sources. A rapid δ13C depletion of ~1‰ in G. bulloides between 20 and 19 ka indicates an early permanent shift in source to a more distal tropical component, likely with an equatorial Pacific contribution that persisted into the Holocene. At 18 ka a smaller, but similar shift in G. inflata δ13C depletion of ~0.3‰, suggests deeper subsurface waters had a delayed reaction to changing conditions during the deglaciation. This contrasts with the isotopic records from nearby Hawke Bay, to the east of the North Island of New Zealand, which exhibited several changes in thermocline depth indicating switches between distal subtropical and proximal subantarctic influences during the early deglaciation ending only after the Antarctic Cold Reversal. Our results identify the mid-latitude subtropics, such as the area around the North Island of New Zealand, as a key region to decipher high versus low latitude influences in Southern Hemisphere shallow water masses.

Turnover in Plants in the North Pacific From the Albian Cretaceous Through the Paleocene Paleogene

Albian-Paleocene flora of the north pacific: Systematic composition, palaeofloristics and phytostratigraphy 

Author:

A. B. Herman

Abstract:

Principal attention is focused on phytostratigraphy and comparative palaeofloristics of the Anadyr-Koryak (AKSR) and Northern Alaska (NASR) subregions of the North Pacific Region. The high-resolution Upper Albian-Paleocene phytostratigraphic schemes of these subregions are based on perceived stages of their floral evolution. In the AKSR the scheme includes seven subdivisions of subregional extent: the Early Ginter (upper Albian), Grebenka (upper Albian-Cenomanian-lower Turonian), Penzhina (upper Turonian), Kaivayam (Coniacian), Barykov (Santonian-lower to ?middle Campanian), Gornorechenian (?upper Campanian-lower Maastrichtian), and Koryak (lower to upper Maastrichtian-?Danian) phytostratigraphic horizons. The phytostratigraphic scheme of the NASR includes three subregional phytostratigraphic horizons and five plant-bearing beds. These are the Kukpowruk (?lower to middle-?upper Albian), Niakogon (upper Albian-Cenomanian), Kaolak (Turonian) horizons and beds with the Tuluvak (Coniacian), Early Kogosukruk (upper Santonian-Campanian), Late Kogosukruk (Campanian-Maastrichtian), Early Sagwon (Danian-Selandian), and Late Sagwon (Selandian-Thanetian) floras. The comparative analysis of coeval (or close in age) floras distinguished in the AKSR and NASR shows that they are either similar to each other (floras Early Ginter and Kukpowruk, Grebenka and Niakogon, Penzhina and Kaolak, Koryak and Early Sagwon) or different in systematic composition (floras Kaivayam and Tuluvak, Gornorechenian and Kogosukruk). Similarities between the floras imply that plant assemblages of two subregions evolved under comparable climatic conditions and freely intercommunicated via the Bering Land Bridge during the Albian-Turonian and terminal Maastrichtian-Paleocene. Floras of the AKSR and NASR, which are of different composition, existed in particular intervals of geological history when trans-Beringian plant migrations were limited or even ceased because of palaeoclimatic difference between the subregions. Floras of the AKSR and NASR survived crisis at the Cretaceous-Paleogene boundary without essential evolutionary consequence which does not support a hypothesis of a global ecological crisis at this boundary. From the analysis of the Arctic end-Cretaceous flora and palaeoclimate we conclude that the large Northern Alaskan dinosaurs were driven by lack of resources (food and shelter) to migrate 1200–1300 kilometres to the South to find forage, warmer temperatures and better light conditions before winter set in. A scenario of the Albian-Late Cretaceous florogenesis in the North Pacific Region is proposed. A primary driver of Albian-Late Cretaceous florogenesis was the gradual invasion by novel angiosperm-rich plant communities into the Asiatic continental interiors and a replacement of pre-existing vegetation dominated by ancient ferns and gymnosperms. Plant fossils representing Mesophytic and Cenophytic communities usually do not mix in the individual assemblages.

Miocene Cooling Tied to Increased Eastern Pacific Upwelling

Middle Miocene climate cooling linked to intensification of eastern equatorial Pacific upwelling

Authors:

Holbourn et al

Abstract:

During the Middle Miocene, Earth's climate transitioned from a relatively warm phase (Miocene climatic optimum) to a colder mode with reestablishment of permanent ice sheets on Antarctica, thus marking a fundamental step in Cenozoic cooling. Carbon sequestration and atmospheric CO2 drawdown through increased terrestrial and/or marine productivity have been proposed as the main drivers of this fundamental transition. We integrate high-resolution (1–3 k.y.) benthic stable isotope data with X-ray fluorescence scanner-derived biogenic silica and carbonate accumulation estimates in an exceptionally well preserved sedimentary archive, recovered at Integrated Ocean Drilling Program Site U1338, to reconstruct eastern equatorial Pacific productivity variations and to investigate temporal links between high- and low-latitude climate change over the interval 16–13 Ma. Our records show that the climatic optimum (16.8–14.7 Ma) was characterized by high-amplitude climate variations, marked by intense perturbations of the carbon cycle. Episodes of peak warmth at (Southern Hemisphere) insolation maxima coincided with transient shoaling of the carbonate compensation depth and enhanced carbonate dissolution in the deep ocean. A switch to obliquity-paced climate variability after 14.7 Ma concurred with a general improvement in carbonate preservation and the onset of stepwise global cooling, culminating with extensive ice growth over Antarctica ca. 13.8 Ma. We find that two massive increases in opal accumulation ca. 14.0 and ca. 13.8 Ma occurred just before and during the final and most prominent cooling step, supporting the hypothesis that enhanced siliceous productivity in the eastern equatorial Pacific contributed to CO2 drawdown.

China Now Actively Patrolling New and Unilateral Air Defense Identification Zone

China sent fighters and an airborne early warning and control (AEW&C) aircraft into its newly declared Air Defence Identification Zone (ADIZ) in the East China Sea on 28 November.

The patrols were the latest move in a series of military moves in Northeast Asia following China's 23 November declaration of the ADIZ. Japan, South Korea and the United States all responded to the ADIZ announcement by sending military aircraft on patrols over the East China Sea.

A People's Liberation Army Air Force (PLAAF) KJ-2000 AEW&C aircraft from the 76th EW (electronic warfare) Regiment, 26th Specialized Division, flew from Wuxi, Jiangsu province, while some PLAAF Sukhoi Su-30 and PLA Navy Air Force Su-27-derived J-11 fighter aircraft also took part in "routine air patrols ... aiming to strengthen monitoring on air targets in the zone and fulfil the air force's historic mission," PLAAF spokesman Colonel Shen Jinke said in a statement posted on the Chinese Ministry of National Defense website.

In its ADIZ announcement China said that all non-Chinese military aircraft within the area that appeared to be approaching Chinese airspace would have to identify themselves and be monitored. Beijing added that Chinese military aircraft would adopt "defensive emergency measures to respond to aircraft that do not co-operate in the identification or refuse to follow the instructions". The statement also said that it would not apply to civilian aircraft on commercial flights.

Japan, South Korea and the United States all said they would ignore the ADIZ. US Secretary of Defense Chuck Hagel said it would "not in any way change how the United States conducts military operations in the region", while in Tokyo, Chief Cabinet Secretary Yoshihide Suga told reporters: "We are not going to change this [our patrols] out of consideration to China."

The ADIZ encompasses the Senkaku/Daioyu islands and at its southernmost point is only 30 km (16 n miles) from the Japanese island of Yonaguni. It overlaps with Japan's own unilaterally imposed ADIZ and also covers Ieodo, a submerged rock that is the source of a territorial dispute between China and South Korea.

The United States followed up Hagel's words by sending two unarmed Boeing B-52 bombers on what it called a "scheduled training mission" from Guam into the East China Sea, where they flew along the southeastern edge of the ADIZ before returning home. Japan announced on 27 November that it had conducted patrols using aircraft from the Japan Self-Defense Forces and Japan Coast Guard in the East China Sea in defiance of the ADIZ, while South Korea announced similar patrols with Republic of Korea Navy aircraft. No Chinese aircraft intercepted these flights.

The Chinese patrol is its second since the ADIZ was announced. On 23 November a Tupolev Tu-154 belonging to the PLA Air Force and a PLA Navy Air Force Shaanxi Y-8 special missions aircraft flew along the part of the edge of China's new ADIZ. Both were tracked - and photographed - by Japan Air Self-Defence Force aircraft.

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Two Borey SSBNs to Join Russian Pacific Fleet in 2014

Two new Project 955 Borey submarines - Vladimir Monomakh and Aleksandr Nevskiy - are expected to join the Pacific Fleet in 2014.

but they don't have ballistic missiles what with the problems with the Bulava SLBM.

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Two USAF B-52 Bombers Fly Through China's Self Declared Air Defense Zone

Two B-52 bombers flew unarmed and unescorted through a no-fly zone declared by China over disputed islands in the East China Sea Monday in a direct challenge by the U.S. to Beijing’s attempts to intimidate its neighbors, defense officials said Tuesday.

The overflight came less than 48 hours after Defense Secretary Chuck Hagel said that the U.S. would not recognize China’s “Air Defense Identification Zone” over the uninhabited Senkaku Islands, claimed by Japan, China and Taiwan.

A Pentagon spokesman, who spoke on condition of anonymity, confirmed that U.S. aircraft flying out of Guam had carried out the overflight on a previously scheduled training mission and returned to Andersen Air Base on Guam “without incident.”

The spokesman would not identify the type of aircraft but other officials said they were B-52H Stratofortresses. In August, B-52s from the 20th Bomber Squadron at Barksdale Air Force Base, La., deployed to Guam as part of the U.S. effort to re-balance forces to the Pacific.

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China/Taiwan Rivalry in Pacific Islands Continues

China will provide a concessionary loan of up to $1 billion to Pacific island nations to support construction projects, state media on Friday cited Vice Premier Wang Yang as saying, a part of the world where Beijing and Taiwan compete for influence.

Wang made the announcement at a forum with Pacific island nations in the southern Chinese city of Guangzhou, the official Xinhua news agency reported. It provided no other details on the loan.

China will also build medical facilities in the region and send medical teams as well as invest in green energy projects, Xinhua cited Wang as saying.

The meeting was attended by representatives from Micronesia, Samoa, Papua New Guinea, Vanuatu, the Cook Islands, Tonga, Niue and Fiji, the news agency added.

The Pacific has traditionally been a site of competition for diplomatic recognition between China and Taiwan, the self-ruled island China claims as its own.

In the region, Taiwan maintains formal ties with Kiribati, Nauru, Palau, the Marshall Islands, the Solomon Islands and Tuvalu. Taiwan has also supported development projects and provided loans.

However, China and Taiwan have maintained an unofficial diplomatic truce and not tried to court each other's allies in the developing world since they signed a series of landmark trade and economic deals in 2008, ushering in improved ties.

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Southern Ocean Responses to a Warmer World

Southwest Pacific Ocean response to a warmer world – insights from Marine Isotope Stage 5e

Authors:

1. G. Cortese (a)
2. G. B. Dunbar (b)
3. L. Carter (b)
4. G. Scott (a)
5. H. Bostock (c)
6. M. Bowen (d)
7. M. Crundwell (a)
8. B. W. Hayward (e)
9. W. Howard (f)
10. J. I. Martínez (g)
11. A. Moy (h,i)
12. H. Neil (c)
13. A. Sabaa (e)
14. A. Sturm (j)

Affiliations:

a. GNS Science, Lower Hutt, New Zealand

b. Antarctic Research Centre, Victoria University of Wellington, Wellington, New Zealand

c. National Institute of Water and Atmospheric Research (NIWA), Wellington, New Zealand

d. School of Environment, University of Auckland, Auckland, New Zealand

e. Geomarine Research, Auckland, New Zealand

f. Research School of Earth Sciences, Australian National University, Canberra, Australia

g. Ciencias del Mar, Dept. of Geology, Universidad EAFIT, Medellin, Colombia

h. Department of Sustainability, Environment, Water, Population and Communities, Australian Antarctic Division, Kingston, Tasmania, Australia

i. Antarctic Climate and Ecosystems Cooperative Research Centre, University of Tasmania, Hobart, Australia

j. Alfred Wegener Institute for Polar and Marine Research, Bremerhaven, Germany

Abstract:

Paleoceanographic archives derived from seventeen marine sediment cores reconstruct the response of the SW Pacific Ocean to the peak interglacial, Marine Isotope Stage (MIS) 5e (ca. 125 ka). Paleo-Sea Surface Temperature (SST) estimates were obtained from the Random Forest model – an ensemble decision tree tool - applied to core-top planktonic foraminiferal faunas calibrated to modern SSTs. The reconstructed geographic pattern of the SST anomaly (maximum SST between 120-132 ka minus mean modern SST) seems to indicate how MIS 5e conditions were generally warmer in the southwest Pacific, especially in the western Tasman Sea where a strengthened East Australian Current (EAC) likely extended subtropical influence to ca. 45oS off Tasmania. In contrast, the eastern Tasman Sea may have had a modest cooling except around 45oS. The observed pattern resembles that developing under the present warming trend in the region. An increase in wind stress curl over the modern South Pacific is hypothesized to have spun-up the South Pacific Subtropical Gyre, with concurrent increase in subtropical flow in the western boundary currents that include the EAC. However, warmer temperatures along the subtropical front and Campbell Plateau to the south suggest the relative influence of the boundary inflows to eastern New Zealand may have differed in MIS 5e, and these currents may have followed different paths compared to today.

Tamu Massif is a Single, Massive Volcano the Size of the State of New Mexico

A University of Houston (UH) professor led a team of scientists to uncover the largest single volcano yet documented on Earth. Covering an area roughly equivalent to the British Isles or the state of New Mexico, this volcano, dubbed the Tamu Massif, is nearly as big as the giant volcanoes of Mars, placing it among the largest in the Solar System.

William Sager, a professor in the Department of Earth and Atmospheric Sciences at UH, first began studying the volcano about 20 years ago at Texas A&M's College of Geosciences. Sager and his team's findings appear in the Sept. 8 issue of Nature Geoscience, the monthly multi-disciplinary journal reflecting disciplines within the geosciences.

Located about 1,000 miles east of Japan, Tamu Massif is the largest feature of Shatsky Rise, an underwater mountain range formed 130 to 145 million years ago by the eruption of several underwater volcanoes. Until now, it was unclear whether Tamu Massif was a single volcano, or a composite of many eruption points. By integrating several sources of evidence, including core samples and data collected on board the JOIDES Resolution research ship, the authors have confirmed that the mass of basalt that constitutes Tamu Massif did indeed erupt from a single source near the center.

"Tamu Massif is the biggest single shield volcano ever discovered on Earth," Sager said. "There may be larger volcanoes, because there are bigger igneous features out there such as the Ontong Java Plateau, but we don't know if these features are one volcano or complexes of volcanoes."

Tamu Massif stands out among underwater volcanoes not just for its size, but also its shape. It is low and broad, meaning that the erupted lava flows must have traveled long distances compared to most other volcanoes on Earth. The seafloor is dotted with thousands of underwater volcanoes, or seamounts, most of which are small and steep compared to the low, broad expanse of Tamu Massif.

link.

That's a VERY interesting time frame.  Oh, about the J-K Boundary even.  Nothing happened then!

Siberian Trap Eruption Projected for 100-200 Million Years in South Pacific

A University of Utah seismologist analyzed seismic waves that bombarded Earth's core, and believes he got a look at the earliest roots of Earth's most cataclysmic kind of volcanic eruption. But don't worry. He says it won't happen for perhaps 200 million years.

"What we may be detecting is the start of one of these large eruptive events that – if it ever happens – could cause very massive destruction on Earth," says seismologist Michael Thorne, the study's principal author and an assistant professor of geology and geophysics at the University of Utah.

But disaster is "not imminent," he adds, "This is the type of mechanism that may generate massive plume eruptions, but on the timescale of 100 million to 200 million years from now. So don't cancel your cruises."

The new study, set for publication this week in the journal Earth and Planetary Science Letters, indicates that two or more continent-sized "piles" of rock are colliding as they move at the bottom of Earth's thick mantle and atop the thicker core some 1,800 miles beneath the Pacific. That is creating a Florida-sized zone of partly molten rock that may be the root of either of two kinds of massive eruptions far in the future:

• Hotspot plume supervolcano eruptions like those during the past 2 million years at Wyoming's Yellowstone caldera, which covered North America with volcanic ash.
• Gargantuan flood basalt eruptions that created "large igneous provinces" like the Pacific Northwest's Columbia River basalts 17 million to 15 million years ago, India's Deccan Traps some 65 million years ago and the Pacific's huge Ontong Java Plateau basalts, which buried an Alaska-sized area 125 million to 199 million years ago.

"These very large, massive eruptions may be tied to some extinction events," Thorne says. The Ontong eruptions have been blamed for oxygen loss in the oceans and a mass die-off of sea life.

Since the early 1990s, scientists have known of the existence of two continent-sized "thermochemical piles" sitting atop Earth's core and beneath most of Earth's volcanic hotspots – one under much of the South Pacific and extending up to 20 degrees north latitude, and the other under volcanically active Africa.

Using the highest-resolution method yet to make seismic images of the core-mantle boundary, Thorne and colleagues found evidence the pile under the Pacific actually is the result of an ongoing collision between two or more piles. Where they are merging is a spongy blob of partly molten rock the size of Florida, Wisconsin or Missouri beneath the volcanically active Samoan hotspot.

The study's computer simulations "show that when these piles merge together, they may trigger the earliest stages of a massive plume eruption," Thorne says.

 Hey!  Think we can get a new mini-continent or at least new New Zealand? That's a fair swap for a second PT event, right?  Good marker for the end of the Cenozoic, too!  SF writers, take note!

This one is a bit odd with the last post in PNAS questioning the reality of plumes.

Did the Quartenary Start with a Bang? An Asteroid Bang?

When a huge meteor collided with Earth about 2.5 million years ago and fell into the southern Pacific Ocean it not only could have generated a massive tsunami but also may have plunged the world into the Ice Ages, a new study suggests.

A team of Australian researchers says that because the Eltanin meteor – which was up to two kilometres across - crashed into deep water, most scientists have not adequately considered either its potential for immediate catastrophic impacts on coastlines around the Pacific rim or its capacity to destabilise the entire planet's climate system.

"This is the only known deep-ocean impact event on the planet and it's largely been forgotten because there's no obvious giant crater to investigate, as there would have been if it had hit a landmass," says Professor James Goff, lead author of a forthcoming paper in the Journal of Quaternary Science. Goff is co-director of UNSW's Australia-Pacific Tsunami Research Centre and Natural Hazards Research Laboratory.

"But consider that we're talking about something the size of a small mountain crashing at very high speed into very deep ocean, between Chile and Antarctica. Unlike a land impact, where the energy of the collision is largely absorbed locally, this would have generated an incredible splash with waves literally hundreds of metres high near the impact site.

"Some modelling suggests that the ensuing mega-tsunami could have been unimaginably large – sweeping across vast areas of the Pacific and engulfing coastlines far inland. But it also would have ejected massive amounts of water vapour, sulphur and dust up into the stratosphere. "The tsunami alone would have been devastating enough in the short term, but all that material shot so high into the atmosphere could have been enough to dim the sun and dramatically reduce surface temperatures. Earth was already in a gradual cooling phase, so this might have been enough to rapidly accelerate and accentuate the process and kick start the Ice Ages."

In the paper, Goff and colleagues from UNSW and the Australian Nuclear Science and Technology Organisation, note that geologists and climatologists have interpreted geological deposits in Chile, Antarctica, Australia, and elsewhere as evidence of climatic change, marking the start of the Quaternary period. An alternative interpretation is that some or all of these deposits may be the result of mega-tsunami inundation, the study suggests.

"There's no doubt the world was already cooling through the mid and late Pliocene," says co-author Professor Mike Archer. "What we're suggesting is that the Eltanin impact may have rammed this slow-moving change forward in an instant - hurtling the world into the cycle of glaciations that characterized the next 2.5 million years and triggered our own evolution as a species.

"As a 'cene' changer - that is, from the Pliocene to Pleistocene - Eltanin may have been overall as significant as the meteor that took out the non-flying dinosaurs 65 million years ago. We're urging our colleagues to carefully reconsider conventional interpretations of the sediments we're flagging and consider whether these could be instead the result of a mega-tsunami triggered by a meteor."

Link.

I suspect that the impact needs to be better constrained for this to be taken past the point of a hypothesis. I find a number of places (like the UCSC image above) that would place the impact at different time periods which would kill the causality.