TREX Glossary
acre-feet
is a unit of volume equal to the volume of a sheet of water one acre in area and one foot in depth; 43,560 cubic feet of water
age trend
a pattern of differing tree ring widths that result from early tree rings tending to be wider than later growth tree rings
anomalies
changes in climate relative to a baseline (example, the average)
archives
historical documents or records (e.g., diaries, notes, official documents, etc)
boreal
of the north or northern regions
climate model
a computer-based simulation of the Earth's climate systems that help us understand past and future climate
cross-dating
is a technique that ensures each individual tree ring is assigned its exact year of formation by matching patterns of wide and narrow rings between cores from the same tree, and between trees from different locations
dendrochronolgist
a scientist that focuses on dating events, environmental changes, and archaeological artifacts by using the characteristic patterns of annual growth rings in timber, tree trunks, and other wood samples
dendrochronology
is the science or technique of dating events, environmental change, and archaeological artifacts by using the characteristic patterns of annual growth rings in timber and tree trunks
detrending
the process of removing the non-climatic trends in the data to show only the absolute changes in tree-ring width and to allow potential cyclical patterns in tree rings to be identified
early wood
is the light colored portion of a tree ring produced in the spring
evapotranspiration
the process by which water is transferred from the land to the atmosphere by evaporation from the soil and other surfaces and by transpiration from plants (moisture loss from stomatal pores on plants)
extremes
unusual or rare climate events
false ring
a layer of wood that appears to look like a complete ring, but is actually just a dark band that is not representative of the end of the growing season. The cellular structure is different than the ring of a complete ring.
Indigenous
The original Peoples of a region, and their descendants, that share distinct cultural traits
instrumental data
weather/climate data collected from instruments at a weather station, for example
late wood
is the darker part of an annual tree ring produced in the summer season
Law of Prior Appropriation
is the legal doctrine that the first person to take a quantity of water from a water source for "beneficial use"—agricultural, industrial or household —has the right to continue to use that quantity of water for that purpose
Little Ice Age
A period of time characterized by cool conditions (~1450-1850 CE), particularly in the North Atlantic region
locally absent rings
are growth rings that are discontinuous around the stem so that it is absent at certain points; also referred to as a partial ring or missing ring
mega drought
is a prolonged drought lasting several years, to decades or longer
oscillation
a repetitive and/or periodic variation over a given time period
paleoclimate
a climate prevalent at a particular time in the geological past
paleoclimatologist
a science discipline that focuses on climatic conditions and their causes and effects in the geologic past using evidence found in glacial deposits, fossils, and sediments
Palmer Drought Severity Index
uses readily available temperature and precipitation data to estimate relative dryness. It is a standardized index that spans -10 (dry) to +10 (wet)
proxy data
is a past climate record like tree rings and ice cores used to interpret paleoclimate
satellite data
an instrument placedin an orbit around Earth that collects information (e.g., imagery) of the Earth's surface
skeleton plot
is a simple graphical representation of the ring width pattern in a sample tree ring core
talus
rock fragments that have accumulated at the base of a cliff or slope
trend
changes in a particular direction
wooly adelgids
small aphid-like insects that suck the sap from young twigs of hemlock, spruce, and fir trees. This prevents tree growth and causes needles to drop prematurely