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Topic Review
Hockey Stick Graph
Hockey stick graphs present the global or hemispherical mean temperature record of the past 500 to 2000 years as shown by quantitative climate reconstructions based on climate proxy records. These reconstructions have consistently shown a slow long term cooling trend changing into relatively rapid warming in the 20th century, with the instrumental temperature record by 2000 exceeding earlier temperatures. The term "hockey stick graph" was popularized by the climatologist Jerry Mahlman, to describe the pattern shown by the Mann, Bradley & Hughes 1999 (MBH99) reconstruction, envisaging a graph that is relatively flat with a downward trend to 1900 as forming an ice hockey stick's "shaft" followed by a sharp, steady increase corresponding to the "blade" portion. The reconstructions have featured in Intergovernmental Panel on Climate Change (IPCC) reports as evidence of global warming. Arguments over the reconstructions have been taken up by fossil fuel industry funded lobbying groups attempting to cast doubt on climate science. Paleoclimatology dates back to the 19th century, and the concept of examining varves in lake beds and tree rings to track local climatic changes was suggested in the 1930s. In the 1960s, Hubert Lamb generalised from historical documents and temperature records of central England to propose a Medieval Warm Period from around 900 to 1300, followed by Little Ice Age. This was the basis of a "schematic diagram" featured in the IPCC First Assessment Report of 1990 beside cautions that the medieval warming might not have been global. The use of indicators to get quantitative estimates of the temperature record of past centuries was developed, and by the late 1990s a number of competing teams of climatologists found indications that recent warming was exceptional. Bradley & Jones 1993 introduced the "Composite Plus Scaling" (CPS) method which, as of 2009, was still being used by most large-scale reconstructions. Their study was featured in the IPCC Second Assessment Report of 1995. In 1998 Michael E. Mann, Raymond S. Bradley and Malcolm K. Hughes developed new statistical techniques to produce Mann, Bradley & Hughes 1998 (MBH98), the first eigenvector-based climate field reconstruction (CFR). This showed global patterns of annual surface temperature, and included a graph of average hemispheric temperatures back to 1400 with shading emphasising that uncertainties (to two standard error limits) were much greater in earlier centuries. Jones et al. 1998 independently produced a CPS reconstruction extending back for a thousand years, and Mann, Bradley & Hughes 1999 (MBH99) used the MBH98 methodology to extend their study back to 1000. A version of the MBH99 graph was featured prominently in the 2001 IPCC Third Assessment Report (TAR), which also drew on Jones et al. 1998 and three other reconstructions to support the conclusion that, in the Northern Hemisphere, the 1990s was likely to have been the warmest decade and 1998 the warmest year during the past 1,000 years. The graph became a focus of dispute for those opposed to the strengthening scientific consensus that late 20th century warmth was exceptional. In 2003, as lobbying over the 1997 Kyoto Protocol intensified, a paper claiming greater medieval warmth was quickly dismissed by scientists in the Soon and Baliunas controversy. Later in 2003, Stephen McIntyre and Ross McKitrick published McIntyre & McKitrick 2003b disputing the data used in MBH98 paper. In 2004 Hans von Storch published criticism of the statistical techniques as tending to underplay variations in earlier parts of the graph, though this was disputed and he later accepted that the effect was very small. In 2005 McIntyre and McKitrick published criticisms of the principal components analysis methodology as used in MBH98 and MBH99. Their analysis was subsequently disputed by published papers including Huybers 2005 and Wahl & Ammann 2007 which pointed to errors in the McIntyre and McKitrick methodology. Political disputes led to the formation of a panel of scientists convened by the United States National Research Council, their North Report in 2006 supported Mann's findings with some qualifications, including agreeing that there were some statistical failings but these had little effect on the result. More than two dozen reconstructions, using various statistical methods and combinations of proxy records, support the broad consensus shown in the original 1998 hockey-stick graph, with variations in how flat the pre-20th century "shaft" appears. The 2007 IPCC Fourth Assessment Report cited 14 reconstructions, 10 of which covered 1,000 years or longer, to support its strengthened conclusion that it was likely that Northern Hemisphere temperatures during the 20th century were the highest in at least the past 1,300 years. Further reconstructions, including Mann et al. 2008 and PAGES 2k Consortium 2013, have supported these general conclusions.
  • 674
  • 10 Nov 2022
Topic Review
Bioburden in Indoor Environments
The exposure to particles and bioaerosols has been associated with the increase in health e ects in children. The objective of this study was to assess the indoor exposure to bioburden in the indoor microenvironments more frequented by children. Air particulate matter (PM) and settled dust were sampled in 33 dwellings and four schools with a medium volume sampler and with a passive method using electrostatic dust collectors (EDC), respectively. Settled dust collected by EDC was analyzed by culture-based methods (including azole resistance profile) and using qPCR.Results showed that the PM2.5 and PM10 concentrations in classrooms were higher than in homes and highly exceeded the limit values established by the Portuguese legislation for indoor air quality. The fungal species most commonly found in bedrooms was Penicillium sp. (91.79%), whereas, in living rooms, it was Rhizopus sp. (37.95%). Aspergillus sections with toxigenic potential were found in bedrooms and living rooms and were able to grow on VOR. 
  • 674
  • 24 Sep 2020
Topic Review
Transnational Municipal Networks
TMNs are considered crucial in creating the framework for political actions against climate change. TMNs give cities the opportunities to directly group themselves into transnational networks active on a specific theme or objective. The recognized importance of these networks is directly linked with the key role cities play in taking actions to mitigate and adapt to climate change.
  • 674
  • 04 Mar 2022
Topic Review
Membrane Biofouling
Water scarcity is an increasing problem on every continent, which instigated the search for novel ways to provide clean water suitable for human use; one such way is desalination. Desalination refers to the process of purifying salts and contaminants to produce water suitable for domestic and industrial applications. Due to the high costs and energy consumption associated with some desalination techniques, membrane-based technologies have emerged as a promising alternative water treatment, due to their high energy efficiency, operational simplicity, and lower cost. However, membrane fouling is a major challenge to membrane-based separation as it has detrimental effects on the membrane’s performance and integrity. Based on the type of accumulated foulants, fouling can be classified into particulate, organic, inorganic, and biofouling. Biofouling is considered the most problematic among the four fouling categories.
  • 674
  • 27 Dec 2022
Topic Review
Sulfide Minerals
The sulfide minerals are a class of minerals containing sulfide (S2−) or persulfide (S22−) as the major anion. Some sulfide minerals are economically important as metal ores. The sulfide class also includes the selenides, the tellurides, the arsenides, the antimonides, the bismuthinides, the sulfarsenides and the sulfosalts. Sulfide minerals are inorganic compounds.
  • 673
  • 24 Oct 2022
Topic Review
Role of Basalt Geochemistry in CO2 Storage
The geochemistry of basalt plays a crucial role in the storage of CO2, as it possesses natural properties that enable the capture and sequestration of CO2. Basalt exhibits a remarkable ability to react with CO2 and form stable carbonate minerals, a process known as mineral carbonation or carbon sequestration.
  • 673
  • 06 Sep 2023
Topic Review
Climate-friendly Gardening
Climate-friendly gardening is gardening in ways which reduce emissions of greenhouse gases from gardens and encourage the absorption of carbon dioxide by soils and plants in order to aid the reduction of global warming. To be a climate-friendly gardener means considering both what happens in a garden and the materials brought into it and the impact they have on land use and climate. It can also include garden features or activities in the garden that help to reduce greenhouse gas emissions elsewhere.
  • 673
  • 11 Oct 2022
Topic Review
Yana, India
Yana is a village located in forests of the Sirsi and Kumta Uttara Kannada district of Karnataka, India which is known for the unusual karst rock formations. It is located in the Sahyadri mountain range of the Western Ghats, about 60 kilometres (37 mi) from Karwar port, 39 kilometres (24 mi) from Sirsi, and 31 kilometres (19 mi) from Kumta. Yana is one of the wettest villages in the world. It is the cleanest village in Karnataka, and the second cleanest village in India . The two unique rock outcrops near the village are a tourist attraction and easily approachable by a small trek through 0.5 kilometres (0.31 mi) of thick forests from the nearest road head. Yana is famous for these two massive rock outcrops known as the Bhairaveshwara Shikhara and the Mohini Shikhara ("Shikhara" means "hill"). The huge rocks are composed of solid black, crystalline karst limestone. Bhairaveshwara Shikhara is 120 metres (390 ft) in height, while the Mohini Shikhara, which is smaller, is 90 metres (300 ft) in height. Yana is also well known as a pilgrimage centre because of the cave temple below the Bhairaveshwara Shikhara where a Swayambhu ("self manifested", or "that which is created by its own accord") linga has been formed. Water drips from the roof over the linga, adding to the sanctity of the place. During Shivaratri here, a car festival is held, along with other festivities. The place and its surrounding hillocks are also known for their evergreen scenic forests.
  • 672
  • 14 Oct 2022
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. 
  • 672
  • 06 Jan 2022
Topic Review
SPE/DLLME for Determining Plasticizer Residues
This entry aims to compare two extraction procedures for the analysis of phthalates (PAE) in hot drinks collected from vending machines, usually coffee and tea. The two analytical procedures rely on solid phase extraction (SPE) using C18 cartridge and ultrasound and vortex assisted liquid-liquid dispersive microextraction (DLLME) to mechanically improve dispersion, each followed by a routine analytical method such as GC- FID. Seven phthalates (DMP, DEP, DiBP, DBP, DEHP, DOP, DDP) were analyzed and determined. All analytical parameters (i.e., recovery, limit of detection, limit of quantification, enrichment factors, repeatability, reproducibility) were studied and discussed, as well as the matrix effect. The whole procedure was applied to hot drink matrices, for example coffee, decaffeinated coffee.
  • 671
  • 13 Sep 2021
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