The “hockey stick” was originally authored by climate scientist Michael Mann and colleagues, and it was first published in Nature in 1998 (here). It showed a reconstruction of northern hemisphere temperatures since A.D. 1400 alongside real-world data from available records.
What is the climate hockey stick?
The climate “hockey stick” refers to a reconstruction of temperatures over the past 1,000 years. The data shows flattish temperatures over the last millennium, like the handle of a Hockey stick, ending in a “blade” of rapidly rising temperatures since the industrial revolution.
What is the hockey stick effect?
The hockey stick effect is characterized by a sharp rise or fall of data points after a long flat period. It is illustrated using the graphical shape of a line chart that resembles a hockey stick.
Why is the hockey stick associated with climate change?
The new study extends the iconic “hockey stick” graph, so named because it showed relatively little temperature rise from AD 1000 to 1900 – and then a very sharp rise in the 20th century when fossil fuel burning started to take effect.
What is the hockey stick debate?
IT IS a persuasive image. Dubbed “the hockey stick” soon after it was first drawn, the graph shows the average temperature over the past 1000 years. Some of the scientists must have hoped that the image would become an icon of climate change. …
What is the greenhouse effect?
The greenhouse effect is the way in which heat is trapped close to Earth’s surface by “greenhouse gases.” These heat-trapping gases can be thought of as a blanket wrapped around Earth, keeping the planet toastier than it would be without them.
What is true about the hockey stick curve?
Like a football, the spinning motion of a Hockey Puck increases stability and accuracy. Control – The Curve of an Ice Hockey Stick Blade greatly increases puck control during stickhandling, especially quick stick handling in tight spaces. It makes it easier to “grab” the puck with your blade without it rolling off.
What does hockey stick mean in economics?
A hockey stick chart is a chart characterized by a sharp increase after a relatively flat and quiet period. … In cases of business sales, a hockey stick chart is represented by a sudden and dramatic increase in sales.
What is hockey stick economic growth?
Hockey stick growth is sudden and extremely rapid growth after a long period of linear growth. The term is often used to describe what happens when a startup business finds its market niche and market conditions are positive.
Where did the hockey stick graph come from?
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 …
What is the hockey stick pattern in Pascal’s Triangle?
The hockey stick identity gets its name by how it is represented in Pascal’s triangle. In Pascal’s triangle, the sum of the elements in a diagonal line starting with 1 is equal to the next element down diagonally in the opposite direction. Circling these elements creates a “hockey stick” shape: 1 + 3 + 6 + 10 = 20.
When was the hockey stick graph created?
The hockey graph was first published in a 1999 paper (pdf) by Michael Mann and colleagues, which was an extension of a 1998 study in Nature. The graph was highlighted in the 2001 report of the Intergovernmental Panel on Climate Change (IPCC).
Why is a field hockey stick curve?
The curved head of a field hockey stick provides a larger surface area with which to stop and hit the hockey ball. Today, the heads of most field hockey sticks are “hooked” upwards. FIH regulations dictate that the head must be J or U shaped and that the hook may not be more than about 4 inches (100mm) deep.
What do tree rings tell us about past climates?
These rings can tell us how old the tree is, and what the weather was like during each year of the tree’s life. The light-colored rings represent wood that grew in the spring and early summer, while the dark rings represent wood that grew in the late summer and fall.
How does Loess help us to learn about climates of the past?
Loess has particular value from the perspective of reconstructing past climates. … Loess units form during periods of peak dust accumulation, typically glacial and stadial periods. Loess can therefore be indicative of cold, arid, and windy climates with reduced vegetation and potentially increased sediment supply.