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. J

    I Variation of Ricci scalar wrt derivative of metric

    I understand from the wiki entry on the Einstein-Hilbert action that: $$\frac{\delta R}{\delta g^{\mu\nu}}=R_{\mu\nu}$$ What is the following? $$\frac{\delta R}{\delta(\partial_\lambda g^{\mu\nu})}$$ Is there a place I could look up such GR expressions on the internet? Thanks
  2. P

    A Parallel plate capacitor in the Rindler metric

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  3. Pyter

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  4. G

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    The ansatz for the 5D metric is \begin{equation} G_{\mu \nu}= g_{\mu \nu}+ \phi A_{\mu} A_{\nu}, \end{equation} \begin{equation} G_{5\nu} = \phi A_{\nu}, \end{equation} \begin{equation} G_{55} = \phi. \end{equation} This information was extremely enlightening for me, but what's the analogous...
  5. V

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  6. P

    A Gauge Invariance of Transverse Traceless Perturbation in Linearized Gravity

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  7. J

    I Metric Signature Choice & Physical Consequences: Exploring Pin(1,3) & Pin(3,1)

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  8. M

    How to Derive the Conservation Law for the FRW Metric?

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  9. robphy

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  10. S

    I Spherically Symmetric Metric: Is Singularity Free?

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  11. George Keeling

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  12. Q

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  13. JD_PM

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  14. K

    I Vanishing of Contraction with Metric Tensor

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  15. J

    I Metric defined with a non-coordinate basis

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  16. Q

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  17. Buzz Bloom

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  18. Buzz Bloom

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  19. Math Amateur

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  20. H

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  21. V

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  22. S

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  23. E

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  24. Q

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  25. S

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  26. N

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  27. E

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  28. P

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  29. M

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  30. D

    I The Tensor & Metric: Spacetime Points & Momentum Flux

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  31. George Keeling

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  32. D

    I Differential Geometry: Comparing Metric Tensors

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  33. R

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  34. R

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  35. Q

    I Minkowski Metric: When to Use It

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  36. M

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  37. W

    I Raising/Lowering Metric Indices: Explained

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  38. Arman777

    I Deriving the area of a spherical triangle from the metric

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  39. P

    I Active Diffeomorphisms of Schwarzschild Metric

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  40. A

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  41. W

    MHB Forecasting metric using regression. Is this a sound approach?

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  42. Pencilvester

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  43. George Keeling

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    Sean Carroll says that if we have metric compatibility then we may lower the index on a vector in a covariant derivative. As far as I know, metric compatibility means ##\nabla_\rho g_{\mu\nu}=\nabla_\rho g^{\mu\nu}=0##, so in that case ##\nabla_\lambda p^\mu=\nabla_\lambda p_\mu##. I can't see...
  44. J

    I How do charts on differentiable manifolds have derivatives without a metric?

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  45. S

    I Godel metric in a cylindrical chart

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  46. W

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  47. Math Amateur

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  48. K

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  49. Math Amateur

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  50. K

    Introduce Newtonian Metric for SR & Lorentz

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