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Climate state describes a state of climate on Earth and similar terrestrial planets based on a thermal energy budget, such as the greenhouse or icehouse climate state. The main climate state change is between periodical glacial and interglacial cycles in Earth history, studied from climate proxies. The climate system is responding to the current climate forcing and adjusts following climate sensitivity to reach a climate equilibrium, Earth's energy balance. Model simulations suggest that the current interglacial climate state will continue for at least another 100,000 years, due to CO2 emissions - including complete deglaciation of the Northern Hemisphere.

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16 Nov 2022

Topic Review

Food security is a measure of the availability of food and individuals' ability to access it. Affordability is only one factor. There is evidence of food security being a concern many thousands of years ago, with central authorities in ancient China and ancient Egypt being known to release food from storage in times of famine. At the 1974 World Food Conference the term "food security" was defined with an emphasis on supply. They said food security is the "availability at all times of adequate, nourishing, diverse, balanced and moderate world food supplies of basic foodstuffs to sustain a steady expansion of food consumption and to offset fluctuations in production and prices". Later definitions added demand and access issues to the definition. The final report of the 1996 World Food Summit states that food security "exists when all people, at all times, have physical and economic access to sufficient, safe and nutritious food to meet their dietary needs and food preferences for an active and healthy life." Household food security exists when all members, at all times, have access to enough food for an active, healthy life. Individuals who are food secure do not live in hunger or fear of starvation. Food insecurity, on the other hand, is defined by the United States Department of Agriculture (USDA) as a situation of "limited or uncertain availability of nutritionally adequate and safe foods or limited or uncertain ability to acquire acceptable foods in socially acceptable ways". Food security incorporates a measure of resilience to future disruption or unavailability of critical food supply due to various risk factors including droughts, shipping disruptions, fuel shortages, economic instability, and wars. In the years 2011–2013, an estimated 842 million people were suffering from chronic hunger. The Food and Agriculture Organization of the United Nations, or FAO, identified the four pillars of food security as availability, access, utilization, and stability. The United Nations (UN) recognized the Right to Food in the Declaration of Human Rights in 1948, and has since said that it is vital for the enjoyment of all other rights. The 1996 World Summit on Food Security declared that "food should not be used as an instrument for political and economic pressure".

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16 Nov 2022

Topic Review

Barcelona (/ˌbɑːrsəˈloʊnə/ BAR-sə-LOH-nə, Catalan: [bəɾsəˈlonə], Spanish: [baɾθeˈlona]) is a city in Spain . It is the capital and largest city of Catalonia, as well as the second most populous municipality of Spain. With a population of 1.6 million within city limits, its urban area extends to numerous neighbouring municipalities within the Province of Barcelona and is home to around 4.8 million people, making it the sixth most populous urban area in the European Union after Paris, London, Madrid, the Ruhr area and Milan. It is one of the largest metropolises on the Mediterranean Sea, located on the coast between the mouths of the rivers Llobregat and Besòs, and bounded to the west by the Serra de Collserola mountain range, the tallest peak of which is 512 metres (1,680 feet) high. Founded as a Roman city, in the Middle Ages Barcelona became the capital of the County of Barcelona. After merging with the Kingdom of Aragon, Barcelona continued to be an important city in the Crown of Aragon as an economic and administrative centre of this Crown and the capital of the Principality of Catalonia. Barcelona has a rich cultural heritage and is today an important cultural centre and a major tourist destination. Particularly renowned are the architectural works of Antoni Gaudí and Lluís Domènech i Montaner, which have been designated UNESCO World Heritage Sites. The headquarters of the Union for the Mediterranean are located in Barcelona. The city is known for hosting the 1992 Summer Olympics as well as world-class conferences and expositions and also many international sport tournaments. Barcelona is one of the world's leading tourist, economic, trade fair and cultural centres, and its influence in commerce, education, entertainment, media, fashion, science, and the arts all contribute to its status as one of the world's major global cities. It is a major cultural and economic centre in southwestern Europe, 24th in the world (before Zürich, after Frankfurt) and a financial centre. In 2008 it was the fourth most economically powerful city by GDP in the European Union and 35th in the world with GDP amounting to €177 billion. In 2012 Barcelona had a GDP of $170 billion; and it was leading Spain in employment rate in that moment. In 2009 the city was ranked Europe's third and one of the world's most successful as a city brand. In the same year the city was ranked Europe's fourth best city for business and fastest improving European city, with growth improved by 17% per year, and the city has been experiencing strong and renewed growth for the past three years. Since 2011 Barcelona has been a leading smart city in Europe. Barcelona is a transport hub, with the Port of Barcelona being one of Europe's principal seaports and busiest European passenger port, an international airport, Barcelona–El Prat Airport, which handles over 40 million passengers per year, an extensive motorway network, and a high-speed rail line with a link to France and the rest of Europe.

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Topic Review

Competitive Enterprise Institute

The Competitive Enterprise Institute (CEI) is a non-profit libertarian think tank founded by political writer Fred L. Smith Jr. on March 9, 1984, in Washington, D.C., to advance principles of limited government, free enterprise, and individual liberty. CEI focuses on a number of regulatory policy issues, including energy, environment, business and finance, labor, technology and telecommunications, transportation, and food and drug regulation. According to the 2017 Global Go To Think Tank Index Report (Think Tanks and Civil Societies Program, University of Pennsylvania), CEI is number 59 (of 60) in the "Top Think Tanks in the United States". Academic research has identified it as one of the Conservative think tanks central to promoting climate change denial.

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16 Nov 2022

Topic Review

Fermented Plant Biomass in Pigs Feeding

The demand for animal-based food production is increasing mainly due to the rapid growth of the human population. The effective production of high-quality agricultural products promotes and protects the natural environment, human health, and animal welfare. Sustainable processing involves minimizing the waste stream. One way to use agricultural plant-based waste, which is often rich in bioactive substances, is to produce fermented feed in accordance with the principles of sustainable development. Corn, yellow lupins, and narrow-leaved lupins are rich in nutrients, and are suitable for fermentation and use in pig feed. They are also safe for weaned piglets. Used as a feed additive, fermented plant biomass has a positive effect on the health of pigs, increasing their weight and improving the taste and appearance of the meat. The fermentation of plant biomass reduces antinutritional substances that are abundant in feed components.

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16 Nov 2022

Topic Review

Cooling Effect of a Green Area

Green façades have a cooling effect on the building and the surrounding climate. Furthermore, the cities are becoming increasingly dense, which makes the space-saving characteristic of vertical greening an optimal solution.

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16 Nov 2022

Topic Review

Conversion of Spent SCR Catalysts into Photocatalysts

Research has explored new recycling methods to convert spent SCR catalysts into products rather than raw materials, such as a pigment and ceramic opacifier. The idea of recycling spent SCR catalysts as photocatalysts for pollution treatment is in-line with the concept of “treating waste with waste”.

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16 Nov 2022

Topic Review

The cryosphere (from the Greek κρύος kryos, "cold", "frost" or "ice" and σφαῖρα sphaira, "globe, ball") is an all-encompassing term for those portions of Earth's surface where water is in solid form, including sea ice, lake ice, river ice, snow cover, glaciers, ice caps, ice sheets, and frozen ground (which includes permafrost). Thus, there is a wide overlap with the hydrosphere. The cryosphere is an integral part of the global climate system with important linkages and feedbacks generated through its influence on surface energy and moisture fluxes, clouds, precipitation, hydrology, atmospheric and oceanic circulation. Through these feedback processes, the cryosphere plays a significant role in the global climate and in climate model response to global changes. The term deglaciation describes the retreat of cryospheric features. Cryology is the study of cryospheres.

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15 Nov 2022

Topic Review

Acid rain has an acidity that is higher than that of normal rainwater. Normal rainwater is not neutral (which would be pH 7) but slightly acidic (it has a pH < 5.5), because some of the carbon dioxide CO2 dissolved in the water is present as carbonic acid H2CO3. In acid rain, chemicals from pollution and natural causes such as volcanic eruptions and emissions from vegetation increase the acidity of the water to as low as pH 4.4 to 4 (as measured in the 1990s in various places). Such acidic rainwater is dangerous for people, vegetation, water bodies including the oceans and its inhabitants, buildings and soil. Since the pH scale is logarithmic, a change from 5.5 to 4.5 means a tenfold increase in acidity. The three main pollutants that cause acid rain are the nitric oxides NO and NO2 (summarized as NOx) and sulfur dioxide SO2. These substances react with water to nitric acid HNO3 and sulfuric acid H2SO4. In the 1980s, in nearly all of Northern Europe and in the Northern United States, suddenly and unexpectedly, whole forests began to die (this effect got to be known as forest dieback). German forests especially experienced severe damage: from 8% in 1982 it increased to 50% in 1984, and stayed as such till 1987. The damage occurred amongst various tree species. Researchers established connections of this damage to acid rain. The mandatory installment of sulfur filters in coal power plants and of catalytic converters in cars in various industrialized countries reduced air pollution with the chemicals related to the formation of acid rain, and, although the forests are still not in perfect shape (about 20% are heavily impaired) a complete death was prevented.

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15 Nov 2022

Topic Review

Mercury's Magnetic Field

Mercury's magnetic field is approximately a magnetic dipole (meaning the field has only two magnetic poles) apparently global, on planet Mercury. Data from Mariner 10 led to its discovery in 1974; the spacecraft measured the field's strength as 1.1% that of Earth's magnetic field. The origin of the magnetic field can be explained by dynamo theory. The magnetic field is strong enough near the bow shock to slow the solar wind, which induces a magnetosphere.

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15 Nov 2022

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