Isotopic labelingIsotopic labeling (or isotopic labelling) is a technique used to track the passage of an isotope (an atom with a detectable variation in neutron count) through a reaction, metabolic pathway, or cell. The reactant is 'labeled' by replacing specific atoms by their isotope. The reactant is then allowed to undergo the reaction. The position of the isotopes in the products is measured to determine the sequence the isotopic atom followed in the reaction or the cell's metabolic pathway.
Human impact on the environmentHuman impact on the environment (or anthropogenic environmental impact) refers to changes to biophysical environments and to ecosystems, biodiversity, and natural resources caused directly or indirectly by humans. Modifying the environment to fit the needs of society (as in the built environment) is causing severe effects including global warming, environmental degradation (such as ocean acidification), mass extinction and biodiversity loss, ecological crisis, and ecological collapse.
Stable isotope ratioThe term stable isotope has a meaning similar to stable nuclide, but is preferably used when speaking of nuclides of a specific element. Hence, the plural form stable isotopes usually refers to isotopes of the same element. The relative abundance of such stable isotopes can be measured experimentally (isotope analysis), yielding an isotope ratio that can be used as a research tool. Theoretically, such stable isotopes could include the radiogenic daughter products of radioactive decay, used in radiometric dating.
Effects of climate changeClimate change affects the physical environment, ecosystems and human societies. Changes in the climate system include an overall warming trend, more extreme weather and rising sea levels. These in turn impact nature and wildlife, as well as human settlements and societies. The effects of human-caused climate change are broad and far-reaching, especially if significant climate action is not taken. The projected and observed negative impacts of climate change are sometimes referred to as the climate crisis.
MacrofossilMacrofossils, also known as megafossils, are preserved organic remains large enough to be visible without a microscope. The term macrofossil stands in opposition to the term microfossil. Microfossils, by contrast, require substantial magnification for evaluation by fossil-hunters or professional paleontologists. As a result, most fossils observed in the field and most "museum-quality" specimens are macrofossils. Plant macrofossils include leaf, needle, cone, and stem debris; and can be used to identify types of plants formerly growing in the area.
Baltic statesThe Baltic states or the Baltic countries is a geopolitical term, which currently is used to group three countries: Estonia, Latvia, and Lithuania. All three countries are members of NATO, the European Union, the Eurozone, and the OECD. The three sovereign states on the eastern coast of the Baltic Sea are sometimes referred to as the "Baltic nations", less often and in historical circumstances also as the "Baltic republics", the "Baltic lands", or simply the Baltics.
Köppen climate classificationThe Köppen climate classification is one of the most widely used climate classification systems. It was first published by German-Russian climatologist Wladimir Köppen (1846–1940) in 1884, with several later modifications by Köppen, notably in 1918 and 1936. Later, German climatologist Rudolf Geiger (1894–1981) introduced some changes to the classification system, which is thus sometimes called the Köppen–Geiger climate classification.
Climate changeIn common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to Earth's climate. The current rise in global average temperature is more rapid than previous changes, and is primarily caused by humans burning fossil fuels. Fossil fuel use, deforestation, and some agricultural and industrial practices increase greenhouse gases, notably carbon dioxide and methane.
Baltic FleetThe Baltic Fleet (Baltiyskiy flot) is the fleet of the Russian Navy in the Baltic Sea. Established 18 May 1703, under Tsar Peter the Great as part of the Imperial Russian Navy, the Baltic Fleet is the oldest Russian fleet. In 1918, the fleet was inherited by the Russian SFSR which then founded the Soviet Union in 1922, where it was eventually known as the Twice Red Banner Baltic Fleet as part of the Soviet Navy, as during this period it gained the two awards of the Order of the Red Banner.
Subarctic climateThe subarctic climate (also called subpolar climate, or boreal climate) is a continental climate with long, cold (often very cold) winters, and short, warm to cool summers. It is found on large landmasses, often away from the moderating effects of an ocean, generally at latitudes from 50°N to 70°N, poleward of the humid continental climates. Subarctic or boreal climates are the source regions for the cold air that affects temperate latitudes to the south in winter.
