Metric Definition and 1000 Threads

METRIC (Mapping EvapoTranspiration at high Resolution with Internalized Calibration) is a computer model developed by the University of Idaho, that uses Landsat satellite data to compute and map evapotranspiration (ET). METRIC calculates ET as a residual of the surface energy balance, where ET is estimated by keeping account of total net short wave and long wave radiation at the vegetation or soil surface, the amount of heat conducted into soil, and the amount of heat convected into the air above the surface. The difference in these three terms represents the amount of energy absorbed during the conversion of liquid water to vapor, which is ET. METRIC expresses near-surface temperature gradients used in heat convection as indexed functions of radiometric surface temperature, thereby eliminating the need for absolutely accurate surface temperature and the need for air-temperature measurements.

The surface energy balance is internally calibrated using ground-based reference ET that is based on local weather or gridded weather data sets to reduce computational biases inherent to remote sensing-based energy balance. Slope and aspect functions and temperature lapsing are used for application to mountainous terrain. METRIC algorithms are designed for relatively routine application by trained engineers and other technical professionals who possess a familiarity with energy balance and basic radiation physics. The primary inputs for the model are short-wave and long-wave thermal images from a satellite e.g., Landsat and MODIS, a digital elevation model, and ground-based weather data measured within or near the area of interest. ET “maps” i.e., images via METRIC provide the means to quantify ET on a field-by-field basis in terms of both the rate and spatial distribution. The use of surface energy balance can detect reduced ET caused by water shortage.
In the decade since Idaho introduced METRIC, it has been adopted for use in Montana, California, New Mexico, Utah, Wyoming, Texas, Nebraska, Colorado, Nevada, and Oregon. The mapping method has enabled these states to negotiate Native American water rights; assess agriculture to urban water transfers; manage aquifer depletion, monitor water right compliance; and protect endangered species.

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  1. Y

    Showing Range of Sequence in Metric Space is Not Always Closed

    Homework Statement show that (the range of) a sequence of points in a metric space is in general not a closed set. Show that it may be a closed set. 2. The attempt at a solution I don't know where to start. For example, if we are given a sequence of real numbers and the distance...
  2. M

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  3. A

    What is a Complete Metric Space in Mathematics?

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  4. Phrak

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  5. D

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  6. E

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  7. jfy4

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  8. S

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  9. pellman

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  10. M

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  11. michael879

    Contravariant metric components

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  12. T

    General Tensor contraction: Trace of Energy-Momentum Tensor (Einstein metric)

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  13. Z

    Question about time dilation in the schwarzchild metric?

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  14. B

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  15. B

    Understanding Disconnectedness in Countable Metric Spaces

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  16. F

    Tortoise-like coordinate transform for interior metric

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  17. J

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  18. B

    Topological and Metric Properties

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  19. A

    Gravitational mass defect, weyl metric

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  20. Y

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  21. C

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  22. Z

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  23. P

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  24. K

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  25. F

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  26. B

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  27. S

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  28. Q

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  29. TrickyDicky

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  30. N

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  31. V

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  32. L

    Kerr Metric Confusion: Problem 1 on Page 138

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  33. M

    Continuity of Metric Spaces: Does the Distance Between Points Remain Consistent?

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  34. Y

    How to calculate the contraction of metric tensor g^ab g_ab

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  35. B

    Is d((xn), (yn)) = lim d(xn, yn) a metric for Cauchy sequences in (X, d)?

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  36. C

    Metric Spaces, Triangle Inequality

    I have the following question on metric spaces Let (X,d) be a metric space and x1,x2,...,xn ∈ X. Show that d(x1, xn) ≤ d(x1, x2) + · · · + d(xn−1, xn2 ), and d(x1, x3) ≥ |d(x1, x2) − d(x2, x3)|. So the first part is simply a statement of the triangle inequality. However, the metric...
  37. Demon117

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  38. T

    Understanding the Usual Metric on R - {0}: A Question from a Homework Statement

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  39. pellman

    Does the metric have to be symmetric? Why?

    Why must we have g_{\mu\nu}=g_{\nu\mu}? What are the physical consequences if this did not hold?
  40. Demon117

    Proof about compact metric spaces.

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  41. L

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  42. C

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  43. W

    Please help. Imposing a metric to preserve distance

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  44. B

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  45. G

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  46. T

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  47. J

    How Do You Convert Cubic Centimeters to Cubic Meters?

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  48. I

    Dark matter, dark energy, and the Kerr metric?

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  49. S

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  50. M

    I proving l^2 is a complete metric space

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