The speed of change in genetic material over time.

A gradual change in genetic material, and the characteristics it codes for, over time.

A few members of a population starts a new population. This new population has less genetic variation.

Mitochondria have their own genetic material, and DNA mutations may accumulate over time.

A point on a graph of ancestry that is used to represent a split of one lineage to form two or more lineages.

Genetic material that exists in the nucleus of the cell.

Here, they mean a process determined by genetics.

Females who had already mated with a different group of male flies.

In neuroscience, a pathway or a circuit refers to a set of neurons that function together to accomplish the same function. Often, these neurons all release the same molecules. Here, the researchers draw our attention to sets of neurons releasing NPF, referring to this as the NPF-NPFR pathway.

There are a number of steps that must occur in order for neuropeptide F to be made in the brain. The first step is for the gene for NPF to be read by the neuron. As the neuron reads this gene, it makes a local copy of it known as a transcript. These transcripts are then recruited by other processes in the cell that use the transcript as an instruction manual about how to build the NPF molecule. Each time a new NPF molecule is made, a new NPF transcript must be created first. For this reason, it is possible to measure the amount of NPF transcripts in the brain in order to determine how much NPF was being produced.

Another experimental method for causing rodents to experience stress in which newly born offspring are taken away from their mothers and raised separately. The lack of a mother present to raise the babies causes them to experience intense stress.

Flies do not have language, but they do communicate with one another in other ways. One such way a fly may communicate is by releasing chemical compounds that other flies can sense, and accordingly respond to. These are known as chemosensory cues. In this case, the authors are referring to chemicals released by the mated female that signal to the male that she is no longer receptive to mating.

In vitro: takes place outside the organism (in a test tube, culture dish, etc.)

In vivo: takes place inside the organism

Changing the function of an enzyme.

Stretches of repeated sequences of nucleic acids (DNA or RNA). Most repetitive regions do not occur in protein-coding genes. However, they are important for regulation.

A domain is a section of a protein that has a specific function.

Systems of enzymes and accessory molecules that carry out cellular functions.

A common method of RNA editing in which the nucleoside adenosine is converted to inosine by the removal of an amino group.

A process when expression of a particular protein is suppressed at the level of RNA.

This is similar to knockout, where the expression of a protein is blocked at the DNA level. Unlike knockout, knockdown can be reversed.

The most widely used method for knockdown is RNA interference.

Cells that are no longer capable of dividing (undergoing mitosis).

Cutting.

Prokaryotes are a class of single-celled organisms with no membrane-bound nucleus, mitochondria, or other membrane-bound organelles.

Examples include bacteria and archaea.

A nuclease is a special enzyme that catalyzes reactions that break down nucleic acids.

A ribonuclease specifically works on RNA molecules.

A type of organic molecule that is made of chains of compounds called nucleotides.

Common examples are DNA and RNA.

Drugs that inhibit the effects of histamines, compounds released by cells in response to inflammatory reactions. These are commonly used to treat allergies.

Describes systems consisting of living organisms. Here, the authors believe that interactions between different microbiota communities may contribute to some variation in genera abundance they could not account for.

Two variables are collinear if they can be predicted from each other accurately, suggesting that they are highly correlated. It is often redundant to have both variables if they are collinear because they can be used as proxies for each other and may hamper interpretation of results.

Refers to anything that has a random probability distribution that can be analyzed statistically, but not precisely predicted. Here, the researchers suggest that some variation in genera abundance might be due to random, uncontrollable factors.

These drugs might include birth control.

A class of psychoactive drugs commonly used to treat anxiety.

This type of medication eases constipation by pulling water back into the colon to soften stool.

Refers to organisms that convert hydrogen into an energy source.

Refers to traits that describe dimensions of the human body; like height, weight, or body fat composition.

A set of data that gives information about another set of data. For example, the author and date describe a document.

Refers to a bioinformatics technique in which the presence or absence of traits across a large number of species can be used to infer biological connections.

A patient's account of their medical history.

A practice in which the storage, shipping, and distribution of samples are continuously kept in a temperature controlled environment. This prevents samples that may be sensitive to temperature fluctuations from degrading.

Plural form of the taxonomic rank, genus.

An exponential distribution is a type of probability distribution, In general, a probability distribution shows the probability that an event (such as a neuron firing) will occur over a given time interval. Specifically, an exponential distribution describes a situation where the probability that the event will occur is proportional to the length of the time interval.

Note: In the image, the x-axis is time, the y-axis is the probability, 1/λ is the mean (average) of the distribution. Each lamda(λ) curve represents an exponential distribution with a different mean.

Spherical structures located near the surface of the antennae lobe in the fly's brain.

Thinly populated. Here, it means that each tag consists of only a small percentage of the neurons present in the olfactory circuit. That is, only a small percentage of neurons fire action potentials in response to the odor.

A type of algorithm that takes a point in a data set and then seeks to find other points in the set that are most similar to it.

Fossil fuels are also called carbonaceous fuels because they are high in carbon compounds.

Part per million (ppm) is a unit of concentration commonly used in atmospheric science and is equivalent to 10\(^{-6}\).

Cloud condensation nuclei (CCN) are small particle that facilitate cloud growth by serving as location of water vapor condensation in the atmosphere. Aerosols often act as surfaced for cloud droplet growth.

The \(\delta\) is a Greek symbol used to represent instantaneous change. Here, the authors are providing a numerical value of the change of aerosol optical depth in the Southern Hemisphere (SH), compared to natural background.

Particles, or aerosols, in the atmosphere, such as dust or smoke, scatter or absorb sunlight. Aerosol optical depth (AOD) tells us how much sunlight was prevented from reaching the surface due to these particles. It is a unitless values that corresponds to the amount of aerosols in the atmosphere over the location where is was measured, often using a satellite.

Sulfate aerosols are formed from the condensation of oxidized sulfur dioxide (SO\(_2\)) emitted from fossil fuels combustion or volcanoes. Because humans are the main source of sulfate aerosols, the concentration of this particle is higher over land in the Northern Hemisphere, which the majority of industrial processes take place. The remainder of this paper provides more details on the different impacts these aerosols have on the Earth system.

Planetary albedo is a measurement of the amount of light reflected from the surface of a planet, in this case, the Earth. Aerosols that reflect more light, such as sulfate aerosols, will enhance the planetary albedo so more incoming solar radiation is reflected back to space. Scientists estimate that Earth's average albedo is 0.3.

Relative humidity (RH) is the ratio of the amount of water vapor in the air (actual vapor density) relative to the amount of water the air could hold (saturation vapor density)

It is given by: \(Relative Humidity\) = \((\dfrac{actual vapor density}{saturation vapor density})\)\(*100%\)

The relative humidity is simply a way for meteorologists and scientists to describe how much moisture is in the air at a give temperature. You and I might feel this on a warm day, where is feels much hotter outside when the humidity is higher.

Hygroscopic means that the particle has the tendency to absorb water or to react with water.

Flux means a change in, so in this case, the authors are referring to a change (in and out) of the global mean top-of-the-atmosphere radiative forcing.

In this case, deliquescent means that the particles absorb moisture.

Measurements of temperature or other weather conditions, such as relative humidity, are called in situ if they are taken in the original location. It is a latin phrase used to differentiate observations taken from satellites, called remote observations.

A mole is an SI unit for the amount of a substance or chemical.

Meteorology is the study of weather, so meteorlogical processes refer to weather events such a winds or thunderstorms.

Longitudes are the imaginary North-South lines drawn on planet Earth so navigators, scientists, and other can establish precise locations.

Some sulfate compounds come from naturally occurring, or biogenic sources, such as dimethylsulfide (DMS) produced from ocean bacteria.

Climate models are numerical representations of the Earth system. Some models are very complex and can take months to run on a supercomputer, others can be run on a laptop in a matter of seconds. More complex models include representations of the atmosphere, oceans, and change in ice dynamics. Simple climate models often represent on the most fundamental physics of the climate system, such as a carbon cycle.

Greenhouse gases (GHGs) absorb outgoing infrared radiation and trap the energy in the atmosphere, causing an increase in temperature over time called greenhouse warming.

Greenhouse gases (GHGs) are atmospheric species that absorb outgoing infrared radiation, such as carbon dioxide (CO\(_2\)) and chlorofluerocarbons (HFCs). GHG have long atmospheric lifetimes ranging from hundreds to thousands of year depending on their chemical and radiative properties. These differences also impacts their radiative forcing abilities.

The troposphere is the area of the atmosphere where you and I live and breathe. It is between 5 - 9 miles thick, depending on your location on Earth. Its name derives from "Tropos”, meaning change, because weather and clouds form in this region of the atmosphere.

Aerosols are small particles suspended in the atmosphere. Sunlight can be absorbed or reflected from the surface of aerosols depending on the size and type of aerosols. These factor determine the atmospheric properties of the aerosol. Aerosols generally have short atmospheric lifetimes compared to greenhouse gases, such as carbon dioxide. For example, black carbon, a type of aerosol emitted from incomplete combustion and biomass burning, have an atmospheric lifetime between 3-5 days.

Tropospheric aerosols are very important to understand because they impact the climate, but also can impact the quality of human health. For example, very fine particles, called Particulate Matter (PM) 2.5, a reference to the diameter of the aerosols in micrometers, are dangerous from humans and leads to increased cardiovascular problems and even death.

Climate scientists generally use the Industrial Revolution as a benchmark in time. Though there is debate in some spheres about the exact date that should be chose, these authors use 1850 to indicate the shift toward industrialization, including use of fossil fuels. Time periods before 1850 are termed "pre-industrial."

The Earth's surface temperature is determined by the balance between incoming solar radiation (sunlight) and outgoing infrared radiation. Radiative forcing (RF) is a measure of the ability of a gas or particle, for example, to effect that energy balance. The units of RF are watt per meter squared (W/m\(^2\)), which translate to the rate of energy change per unit area on the globe as measured from the top of the atmosphere.

Climate change refers to changes in the Earth system from both natural and human factors. Global warming is often use synonymously with climate change, but global warming specifically refers to the rise in global average temperature. More generally, climate change includes the melting of polar ice, increase in ocean acidity, and measured global mean temperature increases.

Anthropogenic means resulting from human activity. Scientists often speak about anthropogenic climate change to specifically discuss the changes resulting from the burning of fossil fuels or land use change, for example.

In this context, marginal means not important or not central.

Any organic substance that is not directly involved in the growth, development, or reproduction of an organism. Vulpinic acid is an example of a secondary metabolite.

A segment of DNA that does not code for proteins and interrupts the sequence of genes.

This is the asexual life stage of fungi, where reproduction is achieved by budding of mononucleated cells.

The shape or form of an organism.

The molecular clock can be adjusted (i.e. calibrated) using fossil data from any taxa represented in a rooted phylogeny, in order to put an approximate date on the nodes of a phylogeny.

Recently, new lichen fossils were found, giving us more insight into the co-evolution of lichen symbionts.

https://blogs.scientificamerican.com/artful-amoeba/new-trove-of-lichen-fossils-expands-total-from-15-to-167/

A group of organisms that clusters together on a phylogenetic tree to the exclusion of all other groups.

In this case, meaning an abnormal outgrowth on the Parmeliaceae thalli.

Plural form of the taxonomic rank, genus.

This is a gene that helps stabilize the ribosome. It is found in all living organisms, so this gene is often used in phylogenetic comparisons of different species.

A taxonomic group of any rank, such as species, family, or class.

The traits that an organism displays. Phenotype results from the interaction of a genotype with the environment.

The gene sequence that an organism carries.

The fungal partner in the lichen symbiosis.

A transcriptome sample that is taken from a collection of organisms. mRNAs must be mapped onto each of the genomes from the organisms in the sample in order to figure out which gene came from which organism. In some cases, there is not a genome available for mapping and instead mRNA is mapped against a large database in order to find a close relative and guess where the mRNA could have come from.

In a laboratory setting; that is, outside of their normal biological context.

Resistance, in this case.

Denotes a laboratory culture that is free from living organisms other than the species required. In this case, lichens could not be formed in a laboratory using only the two known species.

A type of symbiosis in that the relationship is beneficial to both organisms involved.

The outermost layer of the lichen's thallus, where the lichen comes into contact with the environment.

Organisms, often fungi or bacteria, that live within a plant.

Describes how quickly an enzyme can take a single chemical through a specific chemical reaction. It is often abbreviated \(k_{cat}\) like you see here.

A specific statistical method that compares the proportions in a group of samples against those of another group of samples.

Describes where a molecule is in the cell. For example, a protein might be found in the cytoplasm, or it might hang out in a specific organelle.

Commonly accepted. In this case, the hydrolase from Thermobifida fusca is already known to break down PET.

A small chemical that forms the monomer of a protein. Three base pairs in an open reading frame of DNA codes for one amino acid.

These are types of enzymes that are capable of breaking apart certain types of cell compounds. Esterases break down a wide range of compounds called esters. Lipases break down fats and cutinase hydrolyzes cutin, part of the waxy substance you find on leaves.

A process of repairing human-caused damage to the natural environment. For example, environmental remediation might involve removing harmful chemicals from water sources, or removing dangerous radioactive elements from soil. This work is looking at using biological organisms to remove PET film from the environment.

Sometimes a reaction occurs in more than one step. The original material reacts to form what we call a reaction intermediate, which may exist briefly or for a longer period of time, but is later turned into a final product.

In this case, in simplified terms, PET is converted into reaction intermediate MHET (mono(2-hydroxyethyl) terephthalic acid), which is then converted to TPA (terephthalic acid) and EG (ethylene glycol).

The growing material, which contains water, inorganic minerals, and small organic molecules. Most of the microbes in the test tube attached to the PET film, making the liquid culture appear clear.

A chain of two carbon atoms between two oxygen atoms. When two ethylene glycol groups bond to either end of TPA, you get the MHET, the basic monomer of PET. You may have encountered ethylene glycol in the form of anti-freeze.

Silicone is a polymer that is made up of siloxanes. Silicone is used in many household products including baby bottles, adhesives, and skin and hair care products. The smaller the polymer is, the more volatile it will be. Many skin and hair care products use smaller siloxanes which are volatile.

Intermediate Volatile Organic Compounds. Molecules that contain carbon atoms that somewhat evaporate into the gas-phase at typical pressures and temperatures.

Produced from transportation-related activities; for example, driving.

Mobile sources also include off-road engine sources (e.g. construction equipment, lawn mowers, and recreational vehicles), not necessarily related to transportation per se.

A common organic solvent. It has a variety of household uses; acetone is the active ingredient in nail polish remover.

Refers to the lowest portion of the atmosphere, from the surface of Earth out to about 5 miles above the surface.

The troposphere contains all the breathable oxygen in the atmosphere sustaining all life on Earth.

Particles suspended in the air that contain mostly carbon. Soot is a good example of a carbonaceous aerosol.

Unwanted.

The system does not require any additional source of energy.

Spontaneous movement of a substance due to the difference in its concentration between different areas. For example, if you put a tea bag in water, the tea leaves will spread by diffusion, giving the water its color.

Refers to both adsorption and absorption, which are, respectively, the adhesion of a substance to a surface or its incorporation into another substance.

A curve joining points measured at the same temperature. In this case, the water uptake capacity of the MOF is measured by varying either the humidity or the vapor pressure but keeping the temperature constant (isotherm) during the measurement.

Value reflecting the fact that vapor diffusion between different materials is limited by different factors such as the accessibility of the pores.

A device using electricity to transfer heat. Think of it as a refrigerator.

Heat sinks are devices that are used to transfer heat, usually to keep a hot component cool. Although active heat sinks like fans require an input of energy, passive heat sinks are usually made of aluminum fins and rely on their surface area to dissipate heat and do not require energy.

A different metal-organic-framework. The name UiO is used for the MOFs developed at the University of Oslo. This MOF is constituted of the same metal clusters as MOF-801 but with different linkers between them.

The amount of sunlight that reaches the surface.

Constantly changing. In this case, the MOF temperature varies during adsorption and desorption of water.

That releases heat.

The substance adsorbed, in this case water.

Containing holes within its structure.

The amount that passes through a substance. In this case, it is the amount of sunlight received by a surface.

The water present in the atmosphere as vapor, mainly due to evaporation from the oceans.

Structure composed of metal ions linked together by small molecules. This structure repeats itself to form a network that is often porous and can be used to trap chemicals in their cavities like a sponge.

Massachusetts Institute of Technology.

Quantitative measure of the flow of heat between two materials.

Phenomenon through which a substance is released from a surface. In this case, water vapor released from an MOF. It is the opposite of adsorption.

Phenomenon through which a substance adheres to a surface. In this case, water vapor adsorbed to the MOF. It is the opposite of desorption.

The amount of moisture in the air compared to the maximum amount the air can hold at that same temperature.

MOF stands for metal-organic framework. MOF-801 refers to the unique name used to identified this specific metal-organic framework.

A device or substance that absorbs excessive heat.

Using an external source of energy to cool a system, as opposed to passive cooling that does not require energy.

Measure of the capability of the material to allow a substance to pass through the crystal by diffusion.

Distance between the cavities.

Model of diffusion occurring when molecules travel through very small pores.

How well vapor can pass between crystals and through a single crystal by diffusion.

A software used to model and simulate scientific problems.

Stabilized.

Sensors used to measure temperature.

At constant pressure.

The horizontal axis.

The porosity of the final material composed of the MOF in the copper foam.

An ensemble of atoms or molecules linked together.

An apparatus made for turning vapor into liquid.

In this case, the yield is the amount of water that can be harvested.

An energy that cannot be fully converted into another type of energy. Heat is considered a low-grade energy. Low-grade energies are naturally less expensive than high-grade energies such as electricity.

Regions where the speed and variability of climate change are lower than in the surrounding area. These climate refugia have the potential to act as "safe havens" where species can retreat to and persist as the climate changes.

A similar concept is the glacial refugia used by many species during the last ice age. Visit the Encyclopedia of Earth for more information on refugia.

Thermoregulation is the process through which animals increase or decrease their body temperature. Thermoregulation can be done physiologically (e.g. by sweating to cool down during a hot day), or can be done behaviorally (e.g. by taking shelter in the shade during the hottest parts of the day).

Common examples of behavioral thermoregulation are lizards or butterflies basking in the sun. (Photo courtesy Discover Wildlife)

One of eight "realms" that divide Earth's surface. It comprises Europe, North Africa, Asia (north of the Himalayas), and the northern and central Arabian Peninsula. The Palearctic is primarily boreal/subarctic and temperate in climate.

Refers to the thoroughness of people having surveyed a region for species observations. Certain regions and times are more surveyed than others for often mundane reasons, such as accessibility. For example: If a flood washes out the road to a popular park, the park will likely not be searched as often until the road is rebuilt.

These differences in sampling effort between regions and time periods can create trends within the data that are not real. For instance, in the aforementioned example, after the road is washed out and sampling effort decreases, it would appear as if there are less organisms in the park, when in reality there could be the same number of organisms and just fewer people to record them.

In this study, the authors account for differences in sampling intensity by only including species in their study if they had over 100 observations in a baseline time period, and over 30 observations in each other time period.

Describes the evolutionary relationships among organisms (i.e. how related is one organism to another), based off of similarities and differences in physical or genetic characteristics.

Visit here for more information on what phylogenetic trees are and how scientists build them, by Khan Academy.

Tests for a relationship between two or more variables, while accounting for phylogeny (i.e. the fact that some species, or lineages, are more closely related than others).

"Regular" models, such as Generalized least-squares models, or Ordinary least-squares models, also test for a relationship between two or more variables, but these tests assume that variables and species are independent (i.e. are all equally related). When this assumption is violated, the test results can be biased.

Latitudinal range limits are the northernmost and southernmost edges of where a species can be found.

Thermal range limits are the hottest and coldest places of where a species live.

"Georeferenced" means that we know where a species observation was made. This means that we have the latitudinal and longitudinal coordinates for the location where someone found a particular species. It's not just a description of the place, like "third mountain from the left, in Colorado," because that doesn't help us know where a species was found very reliably. These days, it's a lot easier to figure out those coordinates, because most smartphones include GPS that records exactly where something is found. This is the same feature that lets a user track where they are on a map, use Pokémon Go to find an elusive Pokémon, and so on. But instead of finding virtual animals, we can record where the real ones are found. But records from a hundred years ago (obviously) didn't get stored using smartphones, so there's a lot of manual work needed to figure out where those records came from.

Common land-uses include: agriculture, urban space, or wilderness. An intensification of a land-use means that the human influence on the land has increased, but without changing the type of land-use. Typically this includes an increased output of pollutants.

For example, while a pesticide-heavy, monocultured farm field has the same land-use as a pesticide-free organic farm, the intensity of land-use at the monocultured farm would be greater, even if the farms were the same size.

Also known as the soma; is considered to be the cell body of the neuron.

Deoxyribonucleic acid, or DNA for short, is one class of genetic material. It is an example of a nucleic acid molecule.

DNA is composed of three chemical building blocks: a sugar (called deoxyribose), a phosphate group, and a nitrogenous base.

This symbol means "much less than."

When a vector is d-dimensional, d refers to a placeholder value that could stand for any integer, depending on how many feature values are associated with each image.

Hashing is used in computer science to reorganize large data sets (regardless of their size) into tables of fixed size. During this process, multiple data points will typically be stored in the same bin (or hash) based on how similar they are. The hash is then represented with a shortened name, or key, that takes up less storage space in the computer.

In other words, this process helps compress the data so that a computer can use it more efficiently. It also makes it easier and faster to look up data in the table.

![] (https://upload.wikimedia.org/wikipedia/commons/5/58/Hash_table_4_1_1_0_0_1_0_LL.svg)

Not all bees are honeybees! There are actually about 25,000 different species of bees, and the European Honeybee is just one. Bumblebees (genus Bombus) can be distinguished by their fuzzy abdomens and generally larger size.

Check out this infographic from Gould (2015) showing the different families of bees, and "bee hotspots" around the world.

(c) Gould 2015

Also known as assisted colonization or facilitated colonization, is the act of deliberately moving a species to a different habitat, that the species would have eventually occupied given enough time or the removal of another barrier to its natural dispersal. This is in contrast to other types of assisted migrations or species introductions, where species are moved to completely new regions that they would likely never see without human intervention (e.g. the introduction of Cane Toads to Australia, or mongoose in Hawaii).

In this instance, the authors suggest that controlled and carefully managed relocations of bumblebee colonies further north could help these species to track climate change and avoid range compressions.

Indicates a change in where species are found. There are two ways this can happen. First, a species can move into a new place where it never used to be found. Second, a species can disappear (or go locally extinct) from a place where it used to be found.

On the same side as the lesion.

A material with the ability to reflect, refract, and polarize light.

Deep brain region, part of the basal ganglia, composed of glutamatergic neurons and shaped like a lens.

Cells that synthesize and release a compound called dopamine, commonly referred to as a neurotransmitter. Neurotransmitters are released at distant structures of a neuron that come into contact with close or distant cells, called synapses.

Difficult to control or deal with.

Molecules that contain carbon atoms (i.e. organic) and readily evaporate (i.e. volatile) into the gas-phase at typical pressures and temperatures.

In Earth's atmosphere, oxidation generally involves the reaction of a chemical species (such as a VOC) with an oxygen-containing molecule (such as ozone) or a radical (such as OH). The oxidized molecule will generally be less volatile and more water soluble than the starting material. The oxidized product may condense more easily (due to lowered vapor pressure) and form SOA in the atmosphere.

Calculations of how molecules move in air from one location to another. Also accounts for how molecules chemically transform in the atmosphere.

Refers to emissions that occur in the supply chain prior to use by the consumer.

An emission control device that simultaneously removes three air pollutants from tailpipe exhaust by oxidizing carbon monoxide and VOCs, and reducing nitrogen oxides.

Suspended particles in air (dust, soot, water droplets, etc.) that are 2.5 micrometers or smaller in diameter.

Fine particulate matter can be dangerous because the particle size is small enough to be inhaled deep into our lungs. https://blissair.com/what-is-pm-2-5.htm

Small particles that are formed in the atmosphere from the oxidation (a type of chemical reaction) of carbon-containing gases such as VOCs. Later referred to as SOAs in this paper.

Argument count

As part of weather missions, certain aircraft literally penetrate to a storm's center in order to drop sensors that can transmit information about the storm back to the National Hurricane Center.

This supplies data on environmental conditions of different storms in order to directly compare against satellite images.

For more information, check out the "Hurricane Hunters" tab on NOAA"s website: https://www.noaa.gov/explainers/hurricane-forecasting

The Department of Defense in conjunction with the National Oceanic and Atmospheric Administration (NOAA) have access to a fleet of aircraft to conduct hurricane/tropical cyclone reconnaissance, general surveillance, and research missions.

The aircraft take measurements of geographic position, pressure height and altitude, wind direction and speeds, temperature and dew point temperature among others. These data are collected anywhere from every 30 seconds to every half hour while in flight. Up to five reconnaissance missions may go out in a day.

This image shows some of the types of aircraft used by the U.S. to study hurricanes: Image from NOAA's Hurricane Hunters

A pentad is a 5-year period of time.

"Covariability" is the measure of how much two variables vary together. In this case, the authors are looking at whether ocean temperatures and hurricanes vary together.

A confidence level is the probability that the value of a parameter falls within a specified range of values. In this case, the authors are 99% certain that there is an increasing trend in the number of North Atlantic hurricane and storm days.

Total hurricane days = number of days where surface wind speeds remained higher than 33 m s–1.

Tropical storm days = number of days where surface wind speeds remained between 18 and 33 m s–1.

The Saffir-Simpson scale utilizes a hurricanes sustained wind speeds in order to try and estimate potential property damage.

Category 3 hurricanes and higher have the potential for significant loss of life and damage.

Check out the definitions for each category at the National Hurricane Center website: https://www.nhc.noaa.gov/aboutsshws.php

The term "hurricane" is given to systems that develop over the Atlantic or the eastern Pacific Oceans. They are called "typhoons" in the western North Pacific and Philippines. Lastly, they are called "cyclones" in the Indian and South Pacific Ocean.

Using satellite data it is possible to track the development and movement of hurricanes. The tracks that hurricanes progress upon are recorded and stored in online archives typically run by governmental agencies.

For example, the National Hurricane Center compiles past track maps which allow us to look at U.S. landfalling major hurricanes from 2001-2010:

Check out some of the other tracks and data available here: https://www.nhc.noaa.gov/data/?#tracks_all

The U.S. Department of Defense agency responsible for issuing tropical cyclone warnings for the Pacific and Indian Oceans does so through the Joint Typhoon Warning Center, which utilizes satellite data in order to estimate the risk of typhoons and hurricanes of the Pacific and Indian Oceans.

To check out if any storms are currently being watched, visit their website: http://www.metoc.navy.mil/jtwc/jtwc.html

For example from September 19th, 2018:

These authors used a statisical test called the Kendall Test (also known as the Mann Kendall Trend Test or M-K Test) in order to determine if there was a trend through time in the data.

For more information visit: http://www.statisticshowto.com/mann-kendall-trend-test/

"Interannual" means occurring between years or from one year to the next.

Thus this is stating that there is variability in hurricanes from one year to the next due to the effects of large scale climate conditions.

The earliest of Earth's geologic ages. The Precambrian period extends from when Earth began to form around 4.6 billion years ago to 4 billion years ago. EarthViewer provides an interactive way to work through Earth history.

Compounds derived from a plant known as the opium poppy. Originally these came only from natural sources, but now there are synthetic opioids. They are often prescribed for pain relief.

Opiates are considered controlled substances due to their addictive properties. One example is heroin.

A type of chemical messenger. Dopamine levels spike in certain brain regions in response to a reward. They also sometimes spike in anticipation of a reward.

Once the reward is over, dopamine levels will return to normal. Cocaine stops dopamine from being cleared from the synapse by binding to dopamine transporters, so cocaine can cause a larger than normal response, resulting in greater reinforcement.

Skin can become a better or worse conductor of energy/electricity when it is presented with stimuli that represent arousal. When something is physiologically arousing (e.g. scary), the electrical conductance of our skin increases because certain sweat glands become more active. Because of this, skin conductivity is an important indicator of attention and memory function.

Neurons that can be activated by stimuli associated with rewards.

A stimulus that is used to trigger a learned response.

For example, let’s say that you like ice cream, and every time you go to your aunt’s house she gives you your favorite ice cream. Now you tend to associate visiting your aunt with getting ice cream. The stimulus is visiting your aunt, and the association is getting ice cream.

A response that prevents a (usually negative) outcome from occurring.

A test that allows scientists to test for habitual behavior by devaluing certain stimuli that people were trained to associate with a reward. After the stimuli have been devalued, it no longer makes sense to respond to them because there is no longer a reward. If people continue to respond, their behavior is considered habitual.

Behaviors that can help someone escape uncomfortable feelings and unpleasant situations (such as electric shock).

Behaviors that someone develops as a way to respond to their environment, but that end up causing them harm instead of good.

A guide used to classify and diagnose many different mental disorders, such as drug use and dependence.

For substance abuse, some of the considerations are failure to perform normal tasks and functions, legal problems, and physical hazards. For drug dependence, it assesses the need for higher doses, the amount of effort and risk to get the drug, and the persistence of use. All of these must be recurrent problems to be classified as a disorder.