Emergency surveillance for marine pests after the grounding of the container vessel,MV Rena

ABSTRACT

The grounding of the MV Rena in 2011 necessitated urgent entry of salvage vessels into New Zealand. Two, a cargo barge and tug, had been idle in Australia before mobilisation and had well-developed biofouling assemblages that included non-indigenous species new to New Zealand. Surveillance for the species was initiated in Tauranga harbour, Astrolabe Reef and Mōtītī Island, where the vessels had operated. Response personnel were trained to recognise and report the organisms and active surveys were implemented, including reinspection of the vessels after treatment of the biofouling, dive and shoreline searches, and trapping. Although none of the risk species was detected, the biosecurity risk from the vessels changed during the response, from initially acting as a vector for species new to New Zealand to later transporting non-indigenous species from coastal ports to the arena of operations. The study highlights a need for better integration of biosecurity risk management into forward planning for maritime incidents.     

耦合模式FGOALS-g2中大西洋经向翻转流对3个典型浓度路径的响应

利用2个关于大西洋经向翻转流(Atlantic Meridional Overturning Circulation,AMOC)的指数:AMOC指数(15oN~65oN、深度为500 m以下的AMOC的最大值)和AMOC扩展指数(15oN~65oN、深度为2000~2500m的AMOC的最大值),研究了耦合模式FGOALS-g2(Grid-point Version 2 of Flexible Global Ocean-AtmosphereLand System Model)中的AMOC在CMIP5(Coupled Model Intercomparison Project Phase 5)的3个典型浓度路径(Representation Concentration Pathways,RCP)(RCP2.6、RCP4.5和RCP8.5分别对应于2100年时490、650和1370 ppm的CO2浓度水平)下的响应问题,发现:在RCP2.6和RCP4.5浓度路径下,2006~2040年时间段内AMOC指数和AMOC扩展指数都呈现快速下降的趋势,2041~2100年时间段内AMOC指数逐渐恢复,AMOC扩展指数基本维持不变;在RCP8.5浓度路径下,2006~2100年时间段内AMOC指数和AMOC扩展指数都表现出快速下降的趋势。通过分析FGOALS-g2中北大西洋深水的成因发现:3个典型浓度路径下AMOC的长期变化趋势主要受到GIN(Greenland–Iceland–Norwegian)海域的深水形成率的调控,而AMOC的年代际尺度的变化则主要受到Labrador海域深水形成率的控制。同时揭示了:由于北大西洋2000 m深度附近的层结稳定性在RCP2.6和RCP4.5下(相比于1980~2005年)提高了30%~40%,使得由AMOC指数恢复产生的深水无法继续下沉,从而导致AMOC扩展指数没有出现恢复的现象。     

包气带土层对氮素污染地下水的防护能力试验研究

包气带土层能够有效滞留和吸附污染物,是阻隔污染物进入地下水的重要屏障。通过对北京市典型地区包气带土体进行土柱淋溶试验,研究包气带土层对氮素污染地下水的防护能力,实验结果显示,包气带土层对氮素的截污性能具有明显的分段性。粘质粉土对氮素污染地下水具有较强的截留和防护能力,粉砂截留和防护能力相对较差。经计算粘质粉土和粉砂对再生水的净化能力分别为83.3%、29.1%。包气带土层颗粒粒径愈大,污染物浓度高,水动力条件好,包气带土层的防护能力愈差。     

范各庄矿12煤底板突水过程模拟分析

以范各庄煤矿水文地质条件为基础,建立了承压水上采煤的岩体水力学模型,应用岩石破裂过程渗流-应力耦合分析系统(RFPA^2D-Flow)模拟分析了范各庄矿12煤层底板开采扰动下,裂隙形成、扩展到突水通道最终贯通形成突水的全过程。通过对损伤区分布、应力场和渗流场的演化分析,揭示了开采扰动及水压驱动下完整泥岩底板由隔水岩层到突水通道的演化过程,对突水通道进行了模拟定位,并对不同水压条件下含水砂岩层对底板突水的影响进行了分析。结果表明：12煤底板突水问题取决于含水砂岩中的水压力,在假设隔水层厚度不变时,水压力与突水系数呈正相关关系,随着水压的增大突水越易发生。该研究为12煤底板突水预测与防治提供了理论依据。     

塔里木盆地轮南低凸起断裂系统与复式油气聚集

塔里木盆地轮南低凸起复式油气聚集区的提出对高效指导轮南地区的油气勘探起了促进作用。基于区域石油地质研究成果,充分利用成像测井、高分辨三维地震断裂精细描述和有机地球化学等新技术新方法,本文系统研究了轮南低凸起复式油气聚集成藏的关键地质条件,全面刻画了轮南断裂系统的复杂特征,明确了轮南多含油层系具有相同的寒武系海相烃源,证实了在多期次成藏过程中,断裂系统既是早期成藏的油气充注通道,又是晚期调整气侵的输导体系。对轮南海相碳酸盐岩大型油气田的成藏,断裂系统既是有效的储集空间,又是储集性能改善和连通性增强的重要条件,提出复杂断裂系统多期活动下油气渐进幕式成藏和跨越动态成藏模式。从前提(古隆起)、基础(多套储盖组合)和关键(断裂系统)3方面探讨了复式油气聚集成藏的机理,并指出轮古东走滑断裂带是近期扩大轮南复式油气聚集区规模、实施天然气勘探的现实领域。     

IPCC emission scenarios: How did critiques affect their quality and relevance 1990–2022?

Long-term global emission scenarios enable the analysis of future climate change, impacts, and response strategies by providing insight into possible future developments and linking these different climate research elements. Such scenarios play a crucial role in the climate change literature informing the Intergovernmental Panel on Climate Change’s (IPCC) Assessment Reports (ARs) and support policymakers. This article reviews the evolution of emission scenarios, since 1990, by focusing on scenario critiques and responses as published in the literature. We focus on the issues raised in the critiques and the possible impact on scenario development. The critique (280) focuses on four areas: 1) key scenario assumptions (40%), 2) the emissions range covered by the scenarios and missing scenarios (25%), 3) methodological issues (24%), and 4) the policy relevance and handling of uncertainty (11%). Scenario critiques have become increasingly influential since 2000. Some areas of critique have decreased or become less prominent (probability, development process, convergence assumptions, and economic metrics). Other areas have become more dominant over time (e.g., policy relevance & implications of scenarios, transparency, Negative Emissions Technologies (NETs) assumptions, missing scenarios). Several changes have been made in developing scenarios and their content that respond to the critique.     

Petroleum Migration Characteristics in the Northeastern Part of the Baiyun Depression,Pearl River Mouth Basin,South China Sea

This paper investigates the origin and migration characteristics of petroleum in the northeastern part of the Baiyun Depression,Pearl River Mouth Basin(PRMB).The discovered petroleum in the study area is mainly located in the Lower Zhujiang Member(N₁z²)and mainly originated from the Enping Formation source rocks in the eastern sag.Active faults(vertical migration)and N₁z²sandstones(lateral migration)acted as the petroleum migration systems.The fault activities in the Dongsha event controlled the episodic petroleum migration.Fractures in the fault zones provided effective conduits,and overpressure was the driving force.The vertical migration could not cross the fault zones laterally.The petroleum injection areas in the carrier beds were the contact zones of petroleum-migration faults and carrier beds.The lateral migration was steady-state migration,and buoyancy was the driving force.The migration pathways in the carrier beds were controlled by the structural morphology.Secondary petroleum migration in the study area could be divided into two parts:vertical migration along the fractures in the fault zones and lateral migration through preferential petroleum migration pathways(PPMPs)in the carrier beds.The petroleum migration behaviors,including migrating direction,driving force,and migration pattern,in the faults and sandstone carrier beds were quite different.This study provides a typical example for comprehending secondary migration processes and has great importance for determining future exploration targets in the deep-water area of the PRMB.