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112
2009: Understanding El Niño in ocean–atmosphere 23 circulation models: Progress and challenges
"... New community strategies to improve understanding and modeling of El Niño in state-ofthe-art climate models provide opportunities for more accurate tropical climate predictions. The term El Niño was originally used to denote the annual occurrence of a warm ocean current that flows southward along th ..."
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New community strategies to improve understanding and modeling of El Niño in state-ofthe-art climate models provide opportunities for more accurate tropical climate predictions. The term El Niño was originally used to denote the annual occurrence of a warm ocean current that flows southward along the west coast of Peru and Ecuador around Christmas. The term is now used to
AJ (2008) In hot water: Zooplankton and climate change
- ICES Journal of Marine Science
"... An overview is provided of the observed and potential future responses of zooplankton communities to global warming. I begin by describing the importance of zooplankton in ocean ecosystems and the attributes that make them sensitive beacons of climate change. Global warming may have even greater rep ..."
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An overview is provided of the observed and potential future responses of zooplankton communities to global warming. I begin by describing the importance of zooplankton in ocean ecosystems and the attributes that make them sensitive beacons of climate change. Global warming may have even greater repercussions for marine ecosystems than for terrestrial ecosystems, because temp-erature influences water column stability, nutrient enrichment, and the degree of new production, and thus the abundance, size com-position, diversity, and trophic efficiency of zooplankton. Pertinent descriptions of physical changes in the ocean in response to climate change are given as a prelude to a detailed discussion of observed impacts of global warming on zooplankton. These manifest as changes in the distribution of individual species and assemblages, in the timing of important life-cycle events, and in abundance and community structure. The most illustrative case studies, where climate has had an obvious, tangible impact on zooplankton and substantial ecosystem consequences, are presented. Changes in the distribution and phenology of zooplankton are faster and greater than those observed for terrestrial groups. Relevant projected changes in ocean conditions are then presented, followed by an exploration of potential future changes in zooplankton communities from the perspective of different modelling approaches. Researchers have used a range of modelling approaches on individual species and functional groups forced by output from climate models under future greenhouse gas emission scenarios. I conclude by suggesting some potential future directions in climate change research for zooplankton, viz. the use of richer zooplankton functional groups in ecosystem models; greater research effort in tropical systems; investigating climate change in conjunction with other human impacts; and a global zooplankton observing
Earth's Energy Imbalance and Implications
"... Abstract. Improving observations of ocean heat content show that Earth is absorbing more energy from the sun than it is radiating to space as heat, even during the recent solar minimum. The inferred planetary energy imbalance, 0.59 ± 0.15 W/m 2 during the 6-year period 2005-2010, confirms the domina ..."
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Cited by 16 (1 self)
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Abstract. Improving observations of ocean heat content show that Earth is absorbing more energy from the sun than it is radiating to space as heat, even during the recent solar minimum. The inferred planetary energy imbalance, 0.59 ± 0.15 W/m 2 during the 6-year period 2005-2010, confirms the dominant role of the human-made greenhouse effect in driving global climate change. Observed surface temperature change and ocean heat gain together constrain the net climate forcing and ocean mixing rates. We conclude that most climate models mix heat too efficiently into the deep ocean and as a result underestimate the negative forcing by human-made aerosols. Aerosol climate forcing today is inferred to be ‒1.6 ± 0.3 W/m 2, implying substantial aerosol indirect climate forcing via cloud changes. Continued failure to quantify the specific origins of this large forcing is untenable, as knowledge of changing aerosol effects is needed to understand future climate change. We conclude that recent slowdown of ocean heat uptake was caused by a delayed rebound effect from Mount Pinatubo aerosols and a deep prolonged solar minimum. Observed sea level rise during the Argo float era is readily accounted for by ice melt and ocean thermal expansion, but the ascendency of ice melt leads us to anticipate acceleration of the rate of sea level rise this decade.
Interesting times: winners, losers, and system shifts under climate change around Australia
- ICES Journal of Marine Science
"... Feedback and change are basic features of ecosystems, something global change has highlighted. Changes in the physical environment will see shifts in species ranges, community compositions, and ultimately the form and function of ecosystem and the human societies that exploit them. What these shifts ..."
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Cited by 5 (0 self)
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Feedback and change are basic features of ecosystems, something global change has highlighted. Changes in the physical environment will see shifts in species ranges, community compositions, and ultimately the form and function of ecosystem and the human societies that exploit them. What these shifts will be depends on which of the competing (and potentially counteracting) mechanisms dominate through space and time. Moreover, changes are unlikely to be simple or linear; there will be winners, losers, and surprises. It also means that management will be complex and non-stationary, presenting management, scientific, and statistical challenges.
Detection and simulation of heterogeneous fire effects on pyrogenic carbon emissions, tree mortality, and net ecosystem production. Ecosystems
, 2011
"... Fire influences carbon dynamics from local to global scales, but many uncertainties remain regarding the remote detection and simulation of heterogeneous fire effects. This study integrates Landsat-based re-mote sensing and Biome-BGC process modeling to simulate the effects of high-, moderate-, and ..."
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Cited by 4 (0 self)
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Fire influences carbon dynamics from local to global scales, but many uncertainties remain regarding the remote detection and simulation of heterogeneous fire effects. This study integrates Landsat-based re-mote sensing and Biome-BGC process modeling to simulate the effects of high-, moderate-, and low-severity fire on pyrogenic emissions, tree mortality, and net ecosystem production. The simulation area (244,600 ha) encompasses four fires that burned approximately 50,000 ha in 2002–2003 across the Metolius Watershed, Oregon, USA, as well as in situ measurements of postfire carbon pools and fluxes that we use for model evaluation. Simulated total pyrogenic emissions were 0.732 Tg C (2.4 % of equivalent statewide anthropogenic carbon emis-sions over the same 2-year period). The simulated total carbon transfer due to tree mortality was fourfold higher than pyrogenic carbon emissions, but dead wood decomposition will occur over dec-ades. Immediately postfire, burned areas were a simulated carbon source (net C exchange:-0.076 Tg C y-1; mean ± SD:-142 ± 121 g C m-2 y-1). As expected, high-severity, stand-replacement fire had disproportionate carbon impacts. The per-unit area effects of moderate-severity fire were substantial, however, and the extent of low-severity fire merits its inclusion in landscape-scale analyses. These re-sults demonstrate the potential to reduce uncer-tainties in landscape to regional carbon budgets by leveraging Landsat-based fire products that account for both stand-replacement and partial disturbance. Key words: Biome-BGC; carbon modeling; dis-turbance; emission; fire; Landsat; MTBS; net eco-system production; tree mortality.
The Ecological Implications of Sea Level Rise and Storms for Sandy Beaches in KwaZulu-Natal. Master Thesis
- University of KwaZulu-Natal, Durban, South Africa
"... ii The aesthetic appeal of beaches has made coastal properties prime sites for development. However, this development has been mismanaged and is within the littoral active zone. Beaches retreat landwards as sea levels rise, but with current development trends, beaches are trapped in a coastal squeez ..."
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ii The aesthetic appeal of beaches has made coastal properties prime sites for development. However, this development has been mismanaged and is within the littoral active zone. Beaches retreat landwards as sea levels rise, but with current development trends, beaches are trapped in a coastal squeeze. Climate-change predictions include an increase in frequency and heightened intensity of storms, which can cause significant erosion. This study aimed to determine the ecological implications of sea-level rise and storms for beaches in KwaZulu-Natal (KZN), using geographic information systems (GIS) and beach sampling methods. The beaches were mapped in terms of physical and biological attributes. Spatial trends in these attributes showed that the coastline can be split into three – the northern, central and southern regions. Although 25 % of the coastline is protected by marine reserves, these are located in the Delagoa bioregion: 28 macrofauna species in the Natal bioregion are not protected. Storm impacts for beaches can be heterogeneous, depending on local coastal features, e.g., nearshore reef and sand dunes, and represented a temporary disturbance to macrofauna communities. A GIS-based coastal recession model was derived from
Thinking big: a conservation vision for the Southeastern Coastal Plain of North America. Southeastern Naturalist 8
, 2009
"... Abstract -Maps of wild or roadless areas in North America show that most lie west of the Mississippi River. The Everglades is one exception. Yet there are others. Using existing data, I draw attention to four large areas in the southeast that are worthy of national as well as regional attention. Th ..."
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Abstract -Maps of wild or roadless areas in North America show that most lie west of the Mississippi River. The Everglades is one exception. Yet there are others. Using existing data, I draw attention to four large areas in the southeast that are worthy of national as well as regional attention. These four (Eglin: 187,000+ ha; Apalachicola: 228,000+ ha; Okefenokee-Oceola: 289,000+ ha; De Soto: 200,000+ ha) have nearby lands that offer the potential to expand the total protected territory for each area to well beyond 500,000 ha. From the North American perspective, these areas are essential elements of a national conservation plan. These areas urgently need (1) land acquisition to link with nearby protected lands and establish ecologically meaningful boundaries, (2) restoration of natural forces (particularly fl ooding and fi re), and (3) forestry practices focused upon restoration.
A Synthesis of Climate Change and Coastal Science to Support Adaptation
- in the Communities of the Torres Strait. Synthesis Report prepared for the Marine and Tropical Sciences Research Facility. Reef & Rainforest Research Centre Limited
, 2010
"... Supported by the Australian Government’s ..."
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Drilling to Decipher Long-Term Sea-Level Changes and Effects—A
- Joint Consortium for Ocean Leadership, ICDP, IODP, DOSECC, and Chevron Workshop Scientific Drilling
, 2008
"... doi:10.04/iodp.sd.6.0.008 ..."
1273 BIASES IN THE AUSTRALIAN HIGH QUALITY TEMPERATURE NETWORK
"... Various reports identify global warming over the last century as around 0.7°C, but warming in Australia at around 0.9°C, suggesting Australia may be warming faster than the rest of the world. This study evaluates potential biases in the High Quality Network (HQN) compiled from 100 rural surface temp ..."
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Various reports identify global warming over the last century as around 0.7°C, but warming in Australia at around 0.9°C, suggesting Australia may be warming faster than the rest of the world. This study evaluates potential biases in the High Quality Network (HQN) compiled from 100 rural surface temperature series from 1910 due to: (1) homogeneity adjustments used to correct for changes in location and instrumentation, and (2) the discrimination of urban and rural sites. The approach was to compare the HQN with a new network compiled from raw data using the minimal adjustments necessary to produce contiguous series, called the Minimal Adjustment Network (MAN). The average temperature trend of the MAN stations was 31 % lower than the HQN, and by a number of measures, the trend of the Australian MAN is consistent with the global trend. This suggests that biases from these sources have exaggerated apparent Australian warming. Additional problems with the HQN include failure of homogenization procedures to properly identify errors, individual sites adjusted more than the magnitude of putative warming last century, and some sites of such poor quality they should not be used, especially under a “High Quality ” banner. 1.
