.. DO NOT EDIT.
.. THIS FILE WAS AUTOMATICALLY GENERATED BY SPHINX-GALLERY.
.. TO MAKE CHANGES, EDIT THE SOURCE PYTHON FILE:
.. "api/gallery/climate/plot_12_charney_report_sensitivity.py"
.. LINE NUMBERS ARE GIVEN BELOW.

.. only:: html

    .. note::
        :class: sphx-glr-download-link-note

        :ref:`Go to the end <sphx_glr_download_api_gallery_climate_plot_12_charney_report_sensitivity.py>`
        to download the full example code or to run this example in your browser via JupyterLite.

.. rst-class:: sphx-glr-example-title

.. _sphx_glr_api_gallery_climate_plot_12_charney_report_sensitivity.py:


The Charney report's sensitivity range (1979)
=============================================

A panel of the US National Academy of Sciences chaired by Jule Charney
reviewed the climate models of the day. It concluded that doubling CO2 would
warm the Earth by 3 K, probably between 1.5 and 4.5 K. It also warned that
ocean heat capacity would delay the warming by decades. In a one-box model
the delay is the time scale ``C / lambda``, so a more sensitive climate (a
smaller ``lambda``) also responds more slowly.

.. GENERATED FROM PYTHON SOURCE LINES 12-36



.. image-sg:: /api/gallery/climate/images/sphx_glr_plot_12_charney_report_sensitivity_001.png
   :alt: Dots: one e-folding time
   :srcset: /api/gallery/climate/images/sphx_glr_plot_12_charney_report_sensitivity_001.png
   :class: sphx-glr-single-img





.. code-block:: Python


    import matplotlib.pyplot as plt
    import numpy as np

    from earthsciencekit.climate import co2_forcing, equilibrium_warming, heat_capacity_column, response_timescale, step_temperature
    from earthsciencekit.units import convert

    doubling = co2_forcing(560, 280, 5.35)
    capacity = heat_capacity_column(1025, 3990, 100)
    years = np.linspace(0, 100, 401)
    time = convert(years, "year", "s")
    fig, ax = plt.subplots()
    for sensitivity in [1.5, 3.0, 4.5]:
        restoring = doubling / sensitivity
        timescale = response_timescale(capacity, restoring)
        assert np.isclose(equilibrium_warming(doubling, restoring), sensitivity)
        assert np.isclose(step_temperature(doubling, restoring, capacity, timescale), sensitivity * (1 - np.exp(-1)))
        line = ax.plot(years, step_temperature(doubling, restoring, capacity, time), label=f"{sensitivity} K per doubling")[0]
        ax.axhline(sensitivity, color=line.get_color(), ls=":", lw=0.8)
        ax.plot(convert(timescale, "s", "year"), sensitivity * (1 - np.exp(-1)), "o", color=line.get_color())
    ax.set(xlabel="years after doubling", ylabel="warming [K]", title="Dots: one e-folding time")
    ax.legend()

    plt.show()


.. rst-class:: sphx-glr-timing

   **Total running time of the script:** (0 minutes 0.085 seconds)


.. _sphx_glr_download_api_gallery_climate_plot_12_charney_report_sensitivity.py:

.. only:: html

  .. container:: sphx-glr-footer sphx-glr-footer-example

    .. container:: lite-badge

      .. image:: images/jupyterlite_badge_logo.svg
        :target: ../../../lite/lab/index.html?path=api/gallery/climate/plot_12_charney_report_sensitivity.ipynb
        :alt: Launch JupyterLite
        :width: 150 px

    .. container:: sphx-glr-download sphx-glr-download-jupyter

      :download:`Download Jupyter notebook: plot_12_charney_report_sensitivity.ipynb <plot_12_charney_report_sensitivity.ipynb>`

    .. container:: sphx-glr-download sphx-glr-download-python

      :download:`Download Python source code: plot_12_charney_report_sensitivity.py <plot_12_charney_report_sensitivity.py>`

    .. container:: sphx-glr-download sphx-glr-download-zip

      :download:`Download zipped: plot_12_charney_report_sensitivity.zip <plot_12_charney_report_sensitivity.zip>`


.. only:: html

 .. rst-class:: sphx-glr-signature

    `Gallery generated by Sphinx-Gallery <https://sphinx-gallery.github.io>`_