EPA.gov
Climate Change Indicators: Length of Growing Season
Climate Change Indicators: Length of Growing Season | US EPA
This indicator measures the length of the growing season in the contiguous 48 states.
100% REFUTED by USDA and EPA..
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You keep talking about LENGTH of Growing season,
which I haven't once disputed, it is Growing Degree Days (Which is 100% unrelated to length of growing season) that you utterly fail to understand.
The fool keeps ignoring what Growing Degree Days is, tried to help this brain damaged person to understand it, so far he ignores it to talk about
a measure of climate, while I am talking about
a measure of Weather.
Here it is one last time:
"Understanding growing degree-days
Growing degree-days, or heat units, help growers and researchers track the development of plants and pests.
August 25, 2017 - Author: Bob Battel,
Michigan State University Extension
Growing degree-days (GGDs), while not perfect, are a more reliable method of predicting crop and insect development than calendar days. Differing threshold temperatures and beginning accumulation dates are used to determine accumulated heat units for different crops. For example, a cool-season crop like alfalfa uses a threshold temperature of 41 degrees Fahrenheit and a starting date of March 1, whereas a warm-season crop like corn uses a threshold temperature of 50 F and the planting date as the starting date.
The threshold, or base temperature, is the temperature under which no significant crop development is expected. That is, it is assumed alfalfa does not grow at temperatures less than 41 F and corn does not grow at temperatures less than 50 F. Also, an upper-end cutoff temperature is used in the calculation. Crops don’t grow any more at temperatures greater than 86 F than they do at temperatures less than 86 F. Keep that in mind later when we talk about calculating GDDs.
There are two methods for calculating GDD. The first method is simpler and the second method involves higher level mathematics, but is more accurate, especially at cooler temperatures."
bolding and large size words mine
41 and 50 F are well above freezing, but that understanding flew over your bald head."
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From
post one the Village idiot Abu moron, amazingly fails to understand the obvious, since this chart is NOT talking about a literal decrease of growing frost free days, it is talking about a reduction in growing degree days number, as shown inside the link for my own zip code."
"From 1/1/2018 to 9/1/2018, GDD 3316.5
From 1/1/2019 to 9/1/2019, GDD 3023
GDD has decreased in Kennewick, WA to 91.15% of previous value (-8.85% drop) in 99336"
Nothing to do with average length of frost free growing season
, which remains the same.
Growing Degree Days is very different from Growing Frost Free Days.
accumulated growing degrees for that day.
The chart is showing the
DROP of Growing Degree Days over a two year period. It is from 3316.5 to 3023
.
"Growing degree days (GDD) are a measure of heat accumulation used by horticulturists, gardeners, and farmers to predict plant and animal development rates such as the date that a flower will bloom, an insect will emerge from dormancy, or a crop will reach maturity."
Billy_bob produced these numbers showing the approximate drop in total GDD for the map.
Nothing to do with Length of Growing Season.
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Here is an example of what Accumulated Growing Degree days
looks like on a state map:
===========================
Over and over I told Abu the difference and he doesn't get it, that is how stupid he is:
Post 11: Growing Degree Days are
NOT the same as length of growing season!
Post 26: again you make clear you don't understand the
DIFFERENCE between GDD and Length of growing season.
Then at post 20: You are a terrible reader, since post one FOCUSES on
GROWING DEGREE DAYS, you have not addressed this at all. You bring up temperature trends and long term harvest rates.
======
Since it is clear this fool continues to make a fool of himself,
I have dug up this section in the link the warmist fool never read, since he is too busy arguing about something I haven't disputed at all here.
Here is the FORMULA on how to calculate GDD:
Degree-day accumulation = [(Maximum Temperature + Minimum Temperature) / 2] - Base Temperature
Let’s try a couple examples. First, assume a high of 83 F and a low of 61 F on a given day.
The threshold, or base temperature, is the temperature under which no significant crop development is expected. That is, it is assumed alfalfa does not grow at temperatures less than 41 F and corn does not grow at temperatures less than 50 F. Also, an upper-end cutoff temperature is used in the calculation. Crops don’t grow any more at temperatures greater than 86 F than they do at temperatures less than 86 F.
Here it is Abu, Corn Threshold is 50 with a High of 83 and a low of 61, what is the growing degree day number?
To make it really easy for you (Degree-day accumulation base 50 = [(83 + 61) / 2] - 50....) ___?___ accumulated growing degrees for that day.
Realize this is for a SINGLE day. You talk about an entire length of growing season, very different meaning.
Here is the helpful link for you.
Abu tell us what the answer is, it should be easy for you to answer mensa boy.