11: The Seasons of the Sea
- Page ID
- 31576
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\(\newcommand{\avec}{\mathbf a}\) \(\newcommand{\bvec}{\mathbf b}\) \(\newcommand{\cvec}{\mathbf c}\) \(\newcommand{\dvec}{\mathbf d}\) \(\newcommand{\dtil}{\widetilde{\mathbf d}}\) \(\newcommand{\evec}{\mathbf e}\) \(\newcommand{\fvec}{\mathbf f}\) \(\newcommand{\nvec}{\mathbf n}\) \(\newcommand{\pvec}{\mathbf p}\) \(\newcommand{\qvec}{\mathbf q}\) \(\newcommand{\svec}{\mathbf s}\) \(\newcommand{\tvec}{\mathbf t}\) \(\newcommand{\uvec}{\mathbf u}\) \(\newcommand{\vvec}{\mathbf v}\) \(\newcommand{\wvec}{\mathbf w}\) \(\newcommand{\xvec}{\mathbf x}\) \(\newcommand{\yvec}{\mathbf y}\) \(\newcommand{\zvec}{\mathbf z}\) \(\newcommand{\rvec}{\mathbf r}\) \(\newcommand{\mvec}{\mathbf m}\) \(\newcommand{\zerovec}{\mathbf 0}\) \(\newcommand{\onevec}{\mathbf 1}\) \(\newcommand{\real}{\mathbb R}\) \(\newcommand{\twovec}[2]{\left[\begin{array}{r}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\ctwovec}[2]{\left[\begin{array}{c}#1 \\ #2 \end{array}\right]}\) \(\newcommand{\threevec}[3]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\cthreevec}[3]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \end{array}\right]}\) \(\newcommand{\fourvec}[4]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\cfourvec}[4]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \end{array}\right]}\) \(\newcommand{\fivevec}[5]{\left[\begin{array}{r}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\cfivevec}[5]{\left[\begin{array}{c}#1 \\ #2 \\ #3 \\ #4 \\ #5 \\ \end{array}\right]}\) \(\newcommand{\mattwo}[4]{\left[\begin{array}{rr}#1 \amp #2 \\ #3 \amp #4 \\ \end{array}\right]}\) \(\newcommand{\laspan}[1]{\text{Span}\{#1\}}\) \(\newcommand{\bcal}{\cal B}\) \(\newcommand{\ccal}{\cal C}\) \(\newcommand{\scal}{\cal S}\) \(\newcommand{\wcal}{\cal W}\) \(\newcommand{\ecal}{\cal E}\) \(\newcommand{\coords}[2]{\left\{#1\right\}_{#2}}\) \(\newcommand{\gray}[1]{\color{gray}{#1}}\) \(\newcommand{\lgray}[1]{\color{lightgray}{#1}}\) \(\newcommand{\rank}{\operatorname{rank}}\) \(\newcommand{\row}{\text{Row}}\) \(\newcommand{\col}{\text{Col}}\) \(\renewcommand{\row}{\text{Row}}\) \(\newcommand{\nul}{\text{Nul}}\) \(\newcommand{\var}{\text{Var}}\) \(\newcommand{\corr}{\text{corr}}\) \(\newcommand{\len}[1]{\left|#1\right|}\) \(\newcommand{\bbar}{\overline{\bvec}}\) \(\newcommand{\bhat}{\widehat{\bvec}}\) \(\newcommand{\bperp}{\bvec^\perp}\) \(\newcommand{\xhat}{\widehat{\xvec}}\) \(\newcommand{\vhat}{\widehat{\vvec}}\) \(\newcommand{\uhat}{\widehat{\uvec}}\) \(\newcommand{\what}{\widehat{\wvec}}\) \(\newcommand{\Sighat}{\widehat{\Sigma}}\) \(\newcommand{\lt}{<}\) \(\newcommand{\gt}{>}\) \(\newcommand{\amp}{&}\) \(\definecolor{fillinmathshade}{gray}{0.9}\)We now turn our attention to changes in sunlight incident on Earth’s surface that occur as a result of Earth’s orbit around the Sun, what we know as the seasons. These seasonal changes in solar radiation have a profound effect on nature and human activities. The seasonal cycle represents one of the most dynamic and important processes on Earth. The term “season” originated from French and Latin words meaning “to sow or plant.” People in ancient times depended on the planting and harvesting of crops for survival, as they do in modern times. Seasons marked the times when certain farming activities had to be completed. Time off from school during summer—the so-called summer break—arose from the need for young people to help with the planting and harvesting of crops. While fewer modern-day students work on farms than in times past, the tradition of summer break continues to this day. (Aren’t we lucky?)
In the modern age, winter, spring, summer, and fall have special significance in our lives for the clothes we wear, the activities we do, the foods we eat, and the holidays we celebrate. We look forward to the changing seasons. Winter brings snowboarding, spring means Coachella, summer ushers in days at the beach, and fall allows you to dress up like a ghoul. Each new season brings an opportunity to look forward to something, a chance to say, “Next season, I’m going to . . . ”
The ocean has its seasons, too, its own Valentine’s Days, Earth Days, Fourth of Julys, and Halloweens. As the seasons bring changes in the intensity and duration of sunlight, the ocean’s surface cools or warms. Sea ice forms or melts. Plant and animal life diminish or flourish. Like the changing colors of foliage on land, so do the seasons bring changing colors of the ocean, too. In Southern California, the seasonal cycle brings gray whales in winter. It draws beach-nesting grunion fish to our shores in spring, puts forth dazzling tide pool life in summer, and lights the nighttime surf in a blue glow in fall.
In many ways, the seasons of the sea illustrate the most spectacular story of the ocean and its interconnections with life and our planet. Your understanding of the reasons for the seasons provides not only a framework for how the ocean works as a system but also an awareness of its many moods. Each season drives profound shifts in the physics, chemistry, biology, and ultimately the geology of our planet. By the end of this chapter, you’ll have a better appreciation for how and why.