Tag Archives: oceans

Ocean cycles synchronous with global temperature fluctuations

“Now isn’t it a bit odd that the authors made absolutely no mention of the ocean cycles in the abstract? As our regular readers know, the ocean cycles run surprisingly synchronous with the fluctuations in global temperatures, i.e. the key factors here are the AMO and PDO.” click here

Ocean warming only 0.02C since mid-1990s

Carl Wunsch. Towards determining uncertainties in global oceanic mean values of heat, salt, and surface elevation. Journal Tellus A:Dynamic Meteorology and Oceanography Volume 70, 2018 Issue 1, Pages 1-14. https://doi.org/10.1080/16000870.2018.1471911

Lower-bounds on uncertainties in oceanic data and a model are calculated for the 20-year time means and their temporal evolution for oceanic temperature, salinity, and sea surface height, during the data-dense interval 1994–2013. The essential step of separating stochastic from systematic or deterministic elements of the fields is explored by suppressing the globally correlated components of the fields. Justification lies in the physics and the brevity of a 20-year estimate relative to the full oceanic adjustment time, and the inferred near-linearity of response on short time intervals. Lower-bound uncertainties reflecting the only stochastic elements of the state estimate are then calculated from bootstrap estimates. Trends are estimated as  in elevation, 0.0011 ±  0.0001 °C/y, and (−2.825 ± 0.17) × 10−5 for surface elevation, temperature and salt, with formal 2-standard deviation uncertainties. The temperature change corresponds to a 20-year average ocean heating rate of  W/m2 of which 0.1 W/m2 arises from the geothermal forcing. Systematic errors must be determined separately.

 

Poor waste collection primarily responsible for marine pollution

“Executive summary

A marine plastic litter crisis has been declared and the mass media around the world has given their front pages over to the story for a while now. The European Union – among other actors – has declared a war against marine litter. Annually over 10 million metric tons (Mt) of plastic litter end up in oceans, harming wildlife. The International Solid Waste Association (ISWA) – the most competent specialist organization in the field – has summarized the origins of the marine litter crisis: 75% of land based marine litter in low to upper-middle income economies comes from litter and uncollected waste, while the remaining 25% of the land-based sources is plastic which leaks from within the waste management system. In other words, the ISWA report shows that 25% of the leakage is attributable to the waste management option preferred by green ideologues; meanwhile, waste incineration can prevent any leakage of plastic if municipal solid waste (MSW) is incinerated along with sewage sludge. Despite this, incineration is vehemently opposed by green ideologues and also by the EU, which chooses to believe in the mirage of a circular economy. The vast majority of the marine litter problem is attributable to poor waste collection and other sanitary practices in Asian, and to a lesser extent African, towns and cities in coastal areas and along rivers. The problem is particularly acute in China. The neglect of urban sanitary policy – the backbone of development agendas until that time – started when the ‘mother of sustainability’, Norway’s Prime Minister Gro Harlem Brundtland, personally refused to have it be part of her World Commission’s work program and ultimately its 1987 report, which famously led to the adoption of ‘sustainable development’ goals by the UN General Assembly. This report describes the absurdities, inefficiencies, double or even triple waste management structures and horrible consequences of the EU’s erratic green waste policy (such as the terrible waste catastrophe in Naples in 2008), its fact-free claim that its waste policy helps to implement the Paris climate agreement, and its dumping of 3 Mt of plastic in China each year, with horrific consequences for the marine environment and health. The EU has now started to sideline – in the name of circular economy – the highly successful waste incineration policy implemented in seven EU member states – Austria, Belgium, Denmark, Finland, Germany, the Netherlands and Sweden – which all have major waste incineration capacity and now landfill less than 3% of their MSW.” click here

Great Barrier Reef corals can withstand pH variations

McCulloch M.T. et al. (2018) Boron Isotopic Systematics in Scleractinian Corals and the Role of pH Up-regulation. In: Marschall H., Foster G. (eds) Boron Isotopes. Advances in Isotope Geochemistry. Springer, Cham  https://doi.org/10.1007/978-3-319-64666-4_6

The boron isotopic composition (δ11B) of scleractinian corals has been used to track changes in seawater pH and more recently as a probe into the processes controlling bio-calcification. For corals that precipitate aragonite skeletons, up-regulation of pH appears to be a general characteristic, typically being ~0.3 to ~0.6 pH units higher than ambient seawater. The relationship between the pH of the corals calcifying-fluid (pHcf) and seawater pHT (total scale) is shown to be dependent on both physiological as well environmental factors. In laboratory experiments conducted on symbiont-bearing (zooxanthellate) corals under conditions of constant temperature and seawater pH, changes in the δ11B derived calcifying fluid pHcf is typically 1/3 to 1/2 of that of ambient seawater. Similar linear relationships are found for cold water corals that live in relatively stable, cold, deep-water environments but at significantly elevated levels of pHcf(~0.5–1 pH units above seawater), a likely response to the lower pH of their deep-sea environments. In contrast, zooxanthellae-bearing corals living in shallow-water reef environments that experience significant natural variations in temperature, light, nutrients and seawater pH, show different types of responses. For example, over seasonal time-scales Poritescorals from the Great Barrier Reef (GBR) have a large range in pHcf of ~8.3 to ~8.5, significantly greater (~×2 to ~×3) than that of reef-water (pHT ~8.01 to ~8.08), and an order of magnitude greater than that expected from ‘static’ laboratory experiments. Strong physiological controls, but of a different character, are found in corals grown in a Free Ocean Carbon Enrichment Experiment (FOCE) conducted in situ within the Heron Island lagoon (GBR). These corals exhibit near constant pHcf values regardless of external changes in temperature and seawater pH. This pattern of strong physiologically controlled ‘pHhomeostasis’, with elevated but constant pHcf has been found despite large natural seasonal variations in the pH (±0.15 pH units) of the lagoon waters, as well as the even larger super-imposed decreases in seawater pH (~0.25 pH units) designed to simulate year 2100 conditions. In natural reef environments we thus find that the processes influencing the up-regulation of pHcf in symbiont-bearing corals are subject to strong physiological controls, behaviour that is not well simulated in the current generation of aquaria-based experiments with fixed seawater pH and temperature. Conversely, cold-water corals that lack symbionts and inhabit the relatively stable deep-sea environments hold the best prospects for providing reliable reconstructions of seawater pH. Clearly, further studies utilising the δ11B-pHcfproxy combined with other DIC/carbonate-ion proxies (e.g. B/Ca), but conducted under realistic ‘natural’ conditions, are required to elucidate the processes controlling coral bio-calcification and to better understand the vulnerability of scleractinian corals to anthropogenic driven warming and ocean acidification.

No direct effects of ocean acidification observed in Arctic specie

Peter Thor, Fanny Vermandele, Marie-Helene Carignan, Sarah Jacque, Piero Calosi.  No maternal or direct effects of ocean acidification on egg hatching in the Arctic copepod Calanus glacialis PLOS ONE 13(2): e0192496. https://doi.org/10.1371/journal.pone.0192496

Widespread ocean acidification (OA) is transforming the chemistry of the global ocean and the Arctic is recognised as the region where this transformation will occur at the fastest rate. Moreover, many Arctic species are considered less capable of tolerating OA due to their lower capacity for acid-base regulation. This inability may put severe restraints on many fundamental functions, such as growth and reproductive investments, which ultimately may result in reduced fitness. However, maternal effects may alleviate severe effects on the offspring rendering them more tolerant to OA. In a highly replicated experiment we studied maternal and direct effects of OA predicted for the Arctic shelf seas on egg hatching time and success in the keystone copepod species Calanus glacialis. We incubated females at present day conditions (pHT 8.0) and year 2100 extreme conditions (pHT 7.5) during oogenesis and subsequently reciprocally transplanted laid eggs between these two conditions. Statistical tests showed no effects of maternal or direct exposure to OA at this level. We hypothesise that Cglacialis may be physiologically adapted to egg production at low pH since oogenesis can also take place at conditions of potentially low haemolymph pH of the mother during hibernation in the deep.

Evidence lacking for ocean acidification by carbon dioxide

Paul McElhany. CO2 sensitivity experiments are not sufficient to show an effect of ocean acidification. ICES Journal of Marine Science, Volume 74, Issue 4, 1 May 2017, Pages 926–928,https://doi.org/10.1093/icesjms/fsw085

“The ocean acidification (OA) literature is replete with laboratory studies that report species sensitivity to seawater carbonate chemistry in experimental treatments as an “effect of OA”. I argue that this is unintentionally misleading, since these studies do not actually demonstrate an effect of OA but rather show sensitivity to CO2. Documenting an effect of OA involves showing a change in a species (e.g. population abundance or distribution) as a consequence of anthropogenic changes in marine carbonate chemistry. To date, there have been no unambiguous demonstrations of a population level effect of anthropogenic OA, as that term is defined by the IPCC.”

State-of-the-art computer models fail to reproduce recent ocean cooling

Jing-Jia Luo, Gang Wang, Dietmar Dommenget. Many common model biases reduce CMIP5’s ability to simulate the recent Pacific La Niña-like cooling? Climate Dynamics, February 2018, Volume 50, Issue 3–4, pp 1335–1351

Over the recent three decades sea surface temperate (SST) in the eastern equatorial Pacific has decreased, which helps reduce the rate of global warming. However, most CMIP5 model simulations with historical radiative forcing do not reproduce this Pacific La Niña-like cooling. Based on the assumption of “perfect” models, previous studies have suggested that errors in simulated internal climate variations and/or external radiative forcing may cause the discrepancy between the multi-model simulations and the observation. But the exact causes remain unclear. Recent studies have suggested that observed SST warming in the other two ocean basins in past decades and the thermostat mechanism in the Pacific in response to increased radiative forcing may also play an important role in driving this La Niña-like cooling. Here, we investigate an alternative hypothesis that common biases of current state-of-the-art climate models may deteriorate the models’ ability and can also contribute to this multi-model simulations-observation discrepancy. Our results suggest that underestimated inter-basin warming contrast across the three tropical oceans, overestimated surface net heat flux and underestimated local SST-cloud negative feedback in the equatorial Pacific may favor an El Niño-like warming bias in the models. Effects of the three common model biases do not cancel one another and jointly explain ~50% of the total variance of the discrepancies between the observation and individual models’ ensemble mean simulations of the Pacific SST trend. Further efforts on reducing common model biases could help improve simulations of the externally forced climate trends and the multi-decadal climate fluctuations.