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Topic Review

Trewartha Climate Classification

The Trewartha climate classification is a climate classification system first published by American geographer Glenn Thomas Trewartha in 1966. It is a modified version of the Köppen-Geiger system, created to answer some of its deficiencies. The Trewartha system attempts to redefine the middle latitudes to be closer to vegetation zoning and genetic climate systems. It was considered a more true or "real world" reflection of the global climate. The changes were seen as most effective on the large landmasses in Asia and North America, where many areas fall into a single group (C) in the Köppen-Geiger system. For example, under the standard Köppen system, Washington (state) and Oregon are classed into the same climate zone (Csb) as Southern California, even though the two regions have strikingly different weather and vegetation. Another example was classifying cities like London in the same climate group (C) as Brisbane or New Orleans, despite great differences in seasonal temperatures and native plant life.

3.4K
29 Nov 2022

Topic Review

Monitoring Net Land Take in Europe

Land as an environmental resource has gained increasing importance in European policies. The target of “no net land take” by 2050, set by the 2011 Roadmap to a Resource Efficient Europe, is also reinforced by the Soil Strategy of the European Union for 2030. Net land take evaluates, for a given period, the difference between land take and developed land re-naturalization. Its reduction is only feasible by increasing the re-naturalization of developed land, an intervention undertaken in specific and rare circumstances. Accordingly, reusing or recycling developed land is the only intervention that substantially prevents land take. The following defines the three processes for which monitoring is necessary to evaluate the achievement of this target. Then, the legal framework of the European goal is presented, as well as the interventions that can contribute to its pursuit and the actions already taken by some countries and regions in Europe towards this end.

3.4K
13 Jul 2022

Topic Review

Climate Change Maladaptation

Maladaptation is caused by adaptation that fails to reduce vulnerability or inadvertently increases it. Maladaptation can be defined as: ''maladaptation occurs when short-term strategies increase vulnerability in the long term'' or ''action taken ostensibly to avoid or reduce vulnerability to climate change that impacts adversely on, or increase the vulnerability of other systems, sectors, or social groups.''

3.4K
29 Mar 2021

Topic Review

Over Illumination

Over illumination is the presence of lighting intensity higher than that which is appropriate for a specific activity. Over illumination was commonly ignored between 1950 and 1995, especially in office and retail environments. Since then, however, the interior design community has begun to reconsider this practice. Over illumination encompasses two separate concerns: (1) Unnecessary electric lighting is expensive and energy-intensive. Lighting accounts for approximately 9% of residential electricity use (As of 2001) and about 40% of commercial electricity use. (2) Excessive levels of artificial light may adversely affect health. These detrimental effects may depend on the spectrum as well as the overall brightness level of light. Over illumination can be reduced by installing occupancy sensors, using natural sunlight whenever possible, turning off lights when leaving a room, or changing the type of lightbulb. Over illumination does not refer to snowblindness, where high exposure to ultraviolet light causes physical damage to the eye. Too little light, the opposite of over illumination, is associated with seasonal affective disorder.

3.4K
11 Oct 2022

Topic Review

Biodiesel Production from Animal Fats

Animal fats, usually found as waste from slaughterhouses, meat processing industry, and cooking facilities, constitute some of the most relevant waste with costly treatment because environmental regulations are quite strict. Part of such costs may be reduced through the generation of biodiesel that constitutes a valid renewable source of energy because it is biodegradable, non-toxic and has a good combustion emission profile. Furthermore, biodiesel can be blended up to 20% with fossil diesel for its use in many countries. Up to 70% of the total cost of biodiesel majorly depends on the cost of the raw materials used, which can be reduced using animal fat waste because they are cheaper than vegetable oil waste. Transesterification with alkaline catalysis is still preferred at industrial plants producing biodiesel. However, recent developments in technologies for process intensification like ultrasound, microwave, and different types of reactors have been successfully applied in transesterification and improved biodiesel production. Better efficiency has been achieved with new heterogeneous catalysts and nanocatalysts that can be easily recovered, regenerated and reused, and immobilized lipases with increased stability and resistance to alcohol denaturation. Also new adsorbents for increased oxidation stability of biodiesel. All these developments are promising for industrial use in near future.

3.3K
27 Oct 2020

Topic Review

Wireless Sensor Network Technology

Wireless sensor network technology enables distributed sensing through efficient data communication between a multitude of environmental sensors. WSN is still a relatively new area of research, but the communication technology used for low-cost, low-power wireless networks has advanced greatly in recent decades.

3.3K
10 Jan 2023

Topic Review

Kenneth Thomas Cuccinelli II (/ˈkuːtʃɪˈnɛli/ KOO-chi-NEL-ee; born July 30, 1968) is an American politician and lawyer currently serving as Principal Deputy Director of the U.S. Citizenship and Immigration Services (USCIS) agency and Acting Deputy Secretary of Homeland Security. He previously served as the 46th attorney general of Virginia from 2010 until 2014, and acting Director of USCIS agency. Before this, he was in the Virginia Senate, representing the 37th district in Fairfax County from 2002 until he took office as attorney general in 2010. On May 18, 2013, Cuccinelli won the Republican Party's gubernatorial nomination at the state party convention. Cuccinelli was the Republican nominee for Governor of Virginia in the 2013 Virginia gubernatorial election, losing to the Democratic nominee, Terry McAuliffe, by 56,435 votes or 2.5% of the total votes cast. A self-described opponent of homosexuality, Cuccinelli in his position as Virginia Attorney General defended anti-sodomy laws and prohibitions on same-sex marriage. Cuccinelli rejects the scientific consensus on climate change, and in his position as Attorney General investigated climate scientists whom he accused of fraud. He filed lawsuits against the Obama administration’s Environmental Protection Agency. Characterized as an immigration hard-liner, Cuccinelli sought to prohibit undocumented immigrants from attending universities, repeal birthright citizenship, and force employees to speak English in the workplace. As CIS Director, he implemented and defended policies that would reject applications for visas or permanent residency for immigrants considered likely to utilize publicly funded benefits programs.

3.3K
12 Oct 2022

Topic Review Video Peer Reviewed

Three Kinds of Butterfly Effects within Lorenz Models

Within Lorenz models, the three major kinds of butterfly effects (BEs) are the sensitive dependence on initial conditions (SDIC), the ability of a tiny perturbation to create an organized circulation at large distances, and the hypothetical role of small-scale processes in contributing to finite predictability, referred to as the first, second, and third kinds of butterfly effects (BE1, BE2, and BE3), respectively. A well-accepted definition of the butterfly effect is the BE1 with SDIC, which was rediscovered by Lorenz in 1963. In fact, the use of the term “butterfly” appeared in a conference presentation by Lorenz in 1972, when Lorenz introduced the BE2 as the metaphorical butterfly effect. In 2014, the so-called “real butterfly effect”, which is based on the features of Lorenz’s study in 1969, was introduced as the BE3.

3.3K
06 Jul 2022

Topic Review

Phytoremediation

Phytoremediation is defined as the use of plant species as a means of purifying polluted soil, water, and air. The term derives from the Greek word phyto (“plant”) and the Latin word remedium (“to correct or remove an evil”). Phytoremediation is a more economically feasible and efficient remediation option than other techniques, such as washing, flushing, or solidification.

3.3K
13 Feb 2023

Topic Review

Vehicles Exhaust Particulate Matter Emissions

In the automotive field the term “particulate matter (PM)” is used for the collected matter on a flow-through filter under specific conditions, and the term “particle” for aerosol particles measured while airborne (suspended matter). Particles are divided into “volatile” and “non-volatile” (or solid) at tailpipe conditions (high temperature, high concentration). Species that at tailpipe conditions appear volatile, may partition toward the particulate phase at atmospheric conditions (low temperature), and the term semi-volatile better characterizes them. The term “semi-volatiles” (instead of “volatiles”) will be used loosely in this text to indicate species not counted after dilution and thermal pre-treatment at 300–400 °C. The term ultrafine particles (i.e., particles < 100 nm) is not so common in the automotive community. Even though the majority of particles has sizes <100 nm, the tail extends to larger sizes. A recent review argued that a better definition for ultrafine particles (focusing on the automotive field) would be particles <500 nm.

3.3K
09 Feb 2022

Topic Review

Treatment of Petroleum Refinery Wastewater

The treatment of petroleum refinery wastewater (PRWW) is of great interest in industrial wastewater management. This wastewater contains a diverse concentration of contaminants such as oil and grease, petroleum hydrocarbons, phenols, ammonia, and sulfides, as well as other organic and inorganic composites. Refinery wastewater treatment has been attempted through various processes, including physical, biological, chemical, and hybrid methods, which combine two or more techniques.

3.3K
30 Oct 2023

Topic Review

ESG in the Banking Sector

Environmental, Social and Governance (ESG) is currently one of the main focus areas for policy makers worldwide.

3.2K
06 Dec 2021

Topic Review

Urban Heat Island

Economic and social development of urban and rural areas continues in parallel with the increase of the human population, especially in developing countries, which leads to sustained expansion of impervious surface areas, particularly paved surfaces. The conversion of pervious surfaces to impervious surfaces significantly modifies local energy balance in urban areas and contributes to urban heat island (UHI) formation, mainly in densely developed cities. Climate change, urban population growth, and urban land expansion will probably increase temperatures in urban areas and make the UHI effect more prominent. Therefore, using appropriate measures to ameliorate urban microclimate becomes increasingly important.

3.2K
16 Jul 2021

Topic Review

Abandoned Croplands in South Africa

There is no standardised definition of agricultural land abandonment; however, a simple definition is the cessation of agricultural activities on a given surface of land. The term agricultural land abandonment is inclusive of land previously used for crops, vegetables, fruit trees, and cultivated and natural pastures. Other agricultural land abandonment studies specifically focus on crops, hence terms such as cropland abandonment, formerly arable lands, and old arable lands or fields are used. Others specify that for the land to qualify as abandoned, it should not be used for any other activity such as urbanisation or afforestation. Therefore, in the context of the rural areas of Africa wherein the cessation of cropping the land is used for grazing, the definition of cropland abandonment suffices. Baxter and Calvert define cropland abandonment as a process of withdrawing cropland from active agricultural production without a plan for crop cultivation in the immediate future. The cessation is usually due to a decline in economic viability even after changes in farming practices. Cessation results in natural succession wherein grasses, shrubs, and trees colonise former cropping lands; it can also result in land degradation. In the former homeland communal areas of South Africa, where the main agricultural activity involves cropping and livestock production, by default if the land is not used for cropping it turns into a grazing area. The same trend of abandoned cropping lands being used for grazing was also reported in Botswana. Therefore, the definition of abandoned cropping land is land mainly used for grazing. The areas are sometimes also called old fields, fallow, or idle fields. Some have turned to be secondary grasslands.

3.1K
25 May 2022

Topic Review

Tropical Savanna Climate

Tropical savanna climate or tropical wet and dry climate is a type of climate that corresponds to the Köppen climate classification categories Aw (for a dry winter) and As (for a dry summer). Tropical savanna climates have monthly mean temperatures above 18 °C (64 °F) in every month of the year and typically a pronounced dry season, with the driest month having less than 60 mm (2.36 inches) of precipitation and also less than [math]\displaystyle{ 100-\left (\frac{Total\ Annual\ Precipitation\ (mm)}{25} \right) }[/math] of precipitation :200–1 This latter fact is in direct contrast to a tropical monsoon climate, whose driest month sees less than 60 mm of precipitation but has more than [math]\displaystyle{ 100-\left (\frac{Total\ Annual\ Precipitation\ (mm)}{25} \right) }[/math] of precipitation. In essence, a tropical savanna climate tends to either see less rainfall than a tropical monsoon climate or have more pronounced dry season(s). In tropical savanna climates, the dry season can become severe, and often drought conditions prevail during the course of the year. Tropical savanna climates often feature tree-studded grasslands, rather than thick jungle. It is this widespread occurrence of tall, coarse grass (called savanna) which has led to Aw and As climates often being referred to as tropical savanna. However, there is some doubt whether tropical grasslands are climatically induced. Additionally, pure savannas, without trees, are the exception rather than the rule.

3.1K
24 Nov 2022

Topic Review

Leaf area index (LAI)

Leaf area index (LAI) is an important vegetation leaf structure parameter in forest and agricultural ecosystems. Remote sensing techniques can provide an effective alternative to field-based observation of LAI. Different system configurations (passive, active, and multisource sensors on different collection platforms) has been used to estimate forest and crop LAI. The ease of use of empirical models supports these as the preferred choice for forest and crop LAI estimation. In terms of scale issues, both spectral and spatial scales impact the estimation of LAI. Uncertainty coming from various sources results in reduced accuracy in estimating LAI.

3.1K
26 Oct 2020

Topic Review

Public Opinion on Global Warming

Public opinion on global warming is the aggregate of attitudes or beliefs held by the adult population concerning the science, economics, and politics of global warming. It is affected by media coverage of climate change.

3.1K
11 Nov 2022

Topic Review

Tools for Shoreline Change Analysis and Detection

A shoreline is the point of the physical border between land and water. While this definition looks simple, it is indeed challenging in its practical application. The position of the shoreline changes through time due to cross-shore and alongshore sediment movement in the littoral zone, and through changes in water levels. Shoreline change analysis and detection studies have progressed from using simple observation (description) from historical maps and topographical maps to employing high-resolution multi-temporal satellite images with remote sensing and Geographic Information System (GIS) approaches for a better understanding of the subject.

3.1K
05 May 2022

Topic Review

Removal of Inorganic Nitrogen from Wastewater

Water contamination due to various nitrogenous pollutants generated from wastewater treatment plants is a crucial and ubiquitous environmental problem nowadays. Nitrogen contaminated water has manifold detrimental effects on human health as well as aquatic life. Consequently, various biological and bioelectrochemical treatment processes are employed to transform the undesirable forms of nitrogen in wastewater to safer ones for subsequent discharge.

3.0K
27 May 2022

Topic Review

Archimedes Screw Turbines

Archimedes Screws Turbines (ASTs) are a new form of generators for small hydroelectric powerplants that could be applied even in low head sites. ASTs offer a clean and renewable source of energy. They are safer for wildlife and especially fish. The low rotation speed of ASTs reduces negative impacts on aquatic life and fish. Considering the flexibility and advantages of ASTs, they offer economic, social, and environmental advantages to support sustainable development to: - Increase the number of suitable sites and maximize power generation.- Retrofit old dams or upgrade current dams or mills to make them economically (power generation) and environmentally (renewable energy) reasonable.- Reduce the hydroelectricity major operational and/or maintenance costs.- Reduce the disturbance of natural erosion and sedimentation processes.- Make hydropower generation safer for aquatic wildlife, especially for fish.- Generate electricity for small communities, developing countries, and regions with limited access to the power grid or other infrastructures, or regions that are hard to access or connect to the power grid.

3.0K
12 Jan 2022

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