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Topic Review
Temperature Record of the Past 1000 Years
The temperature record of the past 1,000 years or longer is reconstructed using data from climate proxy records in conjunction with the modern instrumental temperature record which only covers the last 170 years at a global scale. Large-scale reconstructions covering part or all of the 1st millennium and 2nd millennium have shown that recent temperatures are exceptional: the Intergovernmental Panel on Climate Change Fourth Assessment Report of 2007 concluded that "Average Northern Hemisphere temperatures during the second half of the 20th century were very likely higher than during any other 50-year period in the last 500 years and likely the highest in at least the past 1,300 years." The curve shown in graphs of these reconstructions is widely known as the hockey stick graph because of the sharp increase in temperatures during the last century. As of 2010 this broad pattern was supported by more than two dozen reconstructions, using various statistical methods and combinations of proxy records, with variations in how flat the pre-20th-century "shaft" appears. Sparseness of proxy records results in considerable uncertainty for earlier periods. Individual proxy records, such as tree ring widths and densities used in dendroclimatology, are calibrated against the instrumental record for the period of overlap. Networks of such records are used to reconstruct past temperatures for regions: tree ring proxies have been used to reconstruct Northern Hemisphere extratropical temperatures (within the tropics trees do not form rings) but are confined to land areas and are scarce in the Southern Hemisphere which is largely ocean. Wider coverage is provided by multiproxy reconstructions, incorporating proxies such as lake sediments, ice cores and corals which are found in different regions, and using statistical methods to relate these sparser proxies to the greater numbers of tree ring records. The "Composite Plus Scaling" (CPS) method is widely used for large-scale multiproxy reconstructions of hemispheric or global average temperatures; this is complemented by Climate Field Reconstruction (CFR) methods which show how climate patterns have developed over large spatial areas, making the reconstruction useful for investigating natural variability and long-term oscillations as well as for comparisons with patterns produced by climate models. During the 1,900 years before the 20th century, it is likely that the next warmest period was from 950 to 1100, with peaks at different times in different regions. This has been called the Medieval Warm Period, and some evidence suggests widespread cooler conditions during a period around the 17th century known as the Little Ice Age. In the hockey stick controversy, contrarians have asserted that the Medieval Warm Period was warmer than at present, and have disputed the data and methods of climate reconstructions.
  • 1.4K
  • 29 Nov 2022
Topic Review
Agricultural Water
Monitoring the microbial quality of water used in agriculture is important to reduce the likelihood of produce contamination and possible future foodborne outbreaks. The U.S. Food and Drug Administration has established the Produce Safety Rule as part of the Food Safety Modernization Act to improve the safety of produce that is normally consumed raw during growing, harvesting, packing and holding activities. In order to comply with the rule, growers need to follow some standards for the microbial quality of water that is used on the produce field, however, more information on the water microbial profile is necessary in order to improve the accuracy of the testing.
  • 1.4K
  • 11 Jan 2022
Topic Review
Water Treatment Residues and Methanogenic Activity in Wastewater-Sludge
The effect of adding alum water treatment residues (WTR) on the methanogenic activity in the digestion of primary domestic wastewater sludge was evaluated through laboratory experiments in sedimentation columns, using total suspended solids (TSS) concentrations from 0.37 to 1.23 g/L. The addition of WTR to primary clarifiers can benefit its effluent water quality in terms of colour, turbidity, chemical oxygen demand (COD), and TSS. However, the presence of WTR can negatively influence the production of methane gas during organic sludge digestion in primary clarifiers, for concentrations of TSS between 14.43 and 25.23 g/L and of VSS between 10.2 and 11.85 g/L. The activity of the Methanothrix sp., curved bacilli, methanococci, and Methanosarcina sp. decreases considerably after 16 days of anaerobic digestion, and methane production seems to only be associated with fluorescent methanogenic bacilli.
  • 1.4K
  • 17 Mar 2022
Topic Review
Looking for Metropolitan ecological area
       Compact housing structures located in city centers are considered to be the most energy and environmentally effective, mainly due to the access to services, transport networks and municipal infrastructures. There is the question how to look for metropolitan ecologacl areas and why so many of the acknowledged ecological housing complexes are located on the outskirts of cities or suburbs and . Numerous cities decide to introduce strategies either to densify city centers, hoping to improve energy efficiency. The Tricity Metropolitan Area is a special case undergoing dynamic transformation, and its development overlaps with the processes of both planned densification of the center as well as uncontrolled suburbanization.  The goal  was to find the correlation between optimal location of an eco-district from the functional center of the Tricity Metropolitan Area, allowing for the most favorable energy and environmental parameters related both to the architectural and urban scale. The research was conducted in four different scenarios, concerning present and future development. In these scenarios, specific locations were examined, and the following were compared: total energy consumption, ecological footprint and CO2 lifecycle emissions. This study showed the possibility for suburban housing complexes with appropriate parameters in an edge city model to have the same or better results than complexes situated closer to the functional center of the city. This is mainly due to the building’s energy efficiency, sustainable mobility, municipal infrastructure and relevant service access. The research proves the importance of implementing sustainable energy-saving and environmentally oriented activities at both an architectural and urban scale planning process.
  • 1.4K
  • 29 Oct 2020
Topic Review
Progesterone on Plant Growth and Development
Progesterone is a steroid hormone that is synthesized in the ovaries, placenta, and adrenal glands. The regulation of progesterone on plant growth is concentration-dependent. For example, low progesterone concentrations (0.01–1 μM) stimulate hypocotyl elongation, while high concentrations (100 μM) inhibit hypocotyl growth in Arabidopsis.
  • 1.4K
  • 14 Oct 2022
Topic Review
Predicted Changing Danube Delta Ecosystems for Fish Species
The Danube Delta is one of Earth’s biodiversity hotspots and includes many endemic, rare, and important species of both major conservation and economic value. This unique complex of ecosystems also plays a key role for Danube River and Black Sea fish fauna through its role as a natural safe buffer, shelter, feeding, reproduction, and smooth transitional area for a large number of fish species. Climate change is inducing a progressive sea level rise in the Black Sea, a fact that is expected to impact the delta’s key complex and dynamic habitats, biocoenoses, and associated biota, and last but not least the key taxonomic group, namely, fish. Around one-third of the fish species of this delta will be greatly affected, sometimes negatively, by this climate change scenario, another one-third to a lesser extent, and the final one-third not at all.
  • 1.4K
  • 20 Jul 2023
Topic Review
Coastal Morphodynamics
The shape of the coast and the processes that mold it change together as a complex system. There is constant feedback among the multiple components of the system, and when climate changes, all facets of the system change. Abrupt shifts to different states can also take place when certain tipping points are crossed. The coupling of rapid warming in the Arctic with melting sea ice is one example of positive feedback. Climate changes, particularly rising sea temperatures, are causing an increasing frequency of tropical storms and “compound events” such as storm surges combined with torrential rains. These events are superimposed on progressive rises in relative sea level and are anticipated to push many coastal morphodynamic systems to tipping points beyond which return to preexisting conditions is unlikely. 
  • 1.4K
  • 02 Nov 2023
Topic Review
E-Waste in Africa
Waste electronic and electrical equipment (e-waste) consists of used and discarded electrical and electronic items ranging from refrigerators to cell phones and printed circuit boards.
  • 1.4K
  • 05 Sep 2021
Topic Review
Biotechnological Approaches Applied for Marine Hydrocarbon Spills Remediation
Biological and physico-chemical remediation technologies can be efficient in terms of spill cleanup and microorganisms—mainly bacteria—are the main ones responsible for petroleum hydrocarbons (PHCs) degradation such as crude oil. Biodegradation is considered as one of the most sustainable and efficient techniques for the removal of PHCs. 
  • 1.4K
  • 18 Jul 2022
Topic Review
Oregon Petition
The Global Warming Petition Project, also known as the Oregon Petition, is a petition urging the United States government to reject the global warming Kyoto Protocol of 1997 and similar policies. Some consider it to be a political petition designed for disinforming and confusing the public about the scientific results and the consensus of climate change research.
  • 1.4K
  • 02 Dec 2022
Topic Review
Biomass Energy Pellets
There is a widespread global shift toward renewable energy sources, where the emphasis is on enhancing the utilization of renewable energy due to the rising costs associated with fossil fuels. In this light, biomass pellets made from woody and non-woody biomass and blends have gained increased attention. Extensive research has been conducted globally to enhance the quality of biomass pellets and to explore the potential to combine woody biomass with other non-woody forms of biomass in biomass pellet production. The heterogeneity of the raw materials used and resulting properties of the biomass pellets have led to the establishment of internationally recognized benchmarks such as the International Organization for Standardization (ISO) 17225 standard to regulate pellet quality.
  • 1.4K
  • 29 Dec 2023
Topic Review
Carbon Sequestration as a Climate Change Mitigation Strategy
Agriculture is the second-highest, after energy use, source of greenhouse gas emissions, which are released from soils and animal digestion processes and as a result of energy consumption at various stages of agricultural production. However, changes in the management of agricultural systems may mitigate the negative impact of this sector on the atmosphere and climate. Carbon farming, which focuses on carbon sequestration, is closely linked to soil quality. Carbon converted to organic form in the soil stimulates the activity of soil enzymes, promotes the growth of beneficial microorganisms and improves chemical and physicochemical properties, including pH, sorption capacity and water retention.
  • 1.4K
  • 13 Jun 2023
Topic Review
Adsorption Techniques for Lead Removal
The long-term sustainability of the global water supply, with a paramount emphasis on cleanliness and safety, stands as a formidable challenge in modern era. In response to this pressing issue, adsorption techniques have emerged as pivotal and widely recognized solutions for the removal of hazardous pollutants, with a particular emphasis on lead adsorption from wastewater.
  • 1.4K
  • 08 Dec 2023
Topic Review
Dioxin
Dioxins and related compounds are environmental xenobiotics that are dangerous to human life, due to the accumulation and persistence in the environment and in the food chain. Cancer, reproductive and developmental issues, and damage to the immune system and endocrine system are only a few examples of the impact of such substances in everyday life. 
  • 1.4K
  • 06 Jan 2022
Topic Review
Mitigation of Global Warming in Australia
Mitigation of global warming involves taking actions to reduce greenhouse gas emissions and to enhance sinks aimed at reducing the extent of global warming. This is in distinction to adaptation to global warming, which involves taking action to minimize the effects of global warming. Scientific consensus on global warming, together with the precautionary principle and the fear of non-linear climate transitions, is leading to increased effort to develop new technologies and sciences and carefully manage others in an attempt to mitigate global warming. In order to make a significant change, coal from Australia needs to be replaced with alternatives. Carbon capture and storage in Australia has been put forward as a solution for production of clean hydrogen from natural gas. Following the introduction of government mandatory renewable energy targets, more opportunities have opened up for renewable energy technologies such as wind power, photovoltaics, and solar thermal technologies. The deployment of these technologies provides opportunities for mitigating greenhouse gases. A carbon price was introduced on 1 July 2012 by the government of Julia Gillard with the purpose of reducing Australia 's carbon emissions. It requires large businesses (defined as those with annual carbon dioxide equivalent emissions over 25,000 tonnes annually) to pay a price for emissions permits. The tax was scrapped by the Abbott government in July 2014 in what was a widely criticized and highly publicized move.
  • 1.4K
  • 12 Oct 2022
Topic Review
Climate, Urbanization and Environmental Pollution in West Africa
The need to elucidate the urbanization–climate–pollution nexus in West Africa arose from the several reported, but disjointed cases of climate extremes and environmental degradation in the sub-region. Since colonization and subsequent independence of nations in the West African region, several urban cities began to spring up and gradually grow. Urbanization was essentially characterized by population growth without complementary infrastructural development, weak coping strategies against climate extremes, numerous economic challenges, and high risk of environmental pollution. Initiative for urban renewal, urban greening and smart city development was low, and preparedness against future impact of extreme climate events and climate change is uncertain.
  • 1.4K
  • 12 Dec 2022
Topic Review
Soil Nanoremediation and Mushrooms
Soil pollution is a serious challenge facing the global community. This pollution is a direct and/or indirect harmful deterioration, which penetrates all aspects of our life, especially human health. Therefore, there is an urgent need to repair, remove, or decompose these pollutants according to various approaches. Concerning the relationship between soil nanoremediation and its mushrooms, this process can be called nano myco-remediation. The mechanism of this kind of remediation depends mainly on the enzymatic system of mushroom species and is involved in the bioremediation of organic environmental pollutants.
  • 1.4K
  • 06 Dec 2022
Topic Review
Salt Lake Aerosols' Chemical Composition and Health Effects
Salt Lakes, having a salt concentration higher than that of seawater and hosting unique extremophiles, are predominantly located in drought-prone zones worldwide, accumulating diverse salts and continuously emitting salt dust or aerosols. Salt Lake aerosols are produced through various processes, including lake-water spray, evaporation-induced salt crystallization, wind-driven dust emissions, microbial activities, chemical reactions, and anthropogenic influences. The primary mechanism involves the breaking of wind-driven waves at the lake surface. As the wind blows across the water, it generates waves. When these waves reach a critical size, they break and release tiny droplets into the air, which become airborne particles and form aerosols.
  • 1.4K
  • 29 Feb 2024
Topic Review
NASA Micropulse Lidar Rain Algorithm
Precipitation modifies atmospheric column thermodynamics through the process of evaporation and serves as a proxy for latent heat modulation. For this reason, a correct precipitation parameterization (especially for low-intensity precipitation) within global scale models is crucial. In addition to improving our modeling of the hydrological cycle, this will reduce the associated uncertainty of global climate models in correctly forecasting future scenarios, and will enable the application of mitigation strategies. In this study we present a proof of concept algorithm to automatically detect precipitation from lidar measurements obtained from the National Aeronautics and Space Administration Micropulse lidar network (MPLNET). 
  • 1.4K
  • 09 Feb 2021
Topic Review
Bacteriophages as Fecal Pollution Indicators
Bacteriophages are promising tools for the detection of fecal pollution in different environments, and particularly for viral pathogen risk assessment. Having similar morphological and biological characteristics, bacteriophages mimic the fate and transport of enteric viruses. For this reason, enteric bacteriophages, especially phages infecting Escherichia coli (coliphages), have been proposed as alternatives or complements to fecal indicator bacteria.
  • 1.4K
  • 25 Jun 2021
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