Introduction to Lecture 14: Tides, Biological Productivity

Bay of Fundy -- low tide, Photo by Dylan Kereluk, . Creative Commons A 2.0 Generic, http://commons.wikimedia.org/wiki/File:Bay_of_Fundy_-_Tide_Out.jpg

Introduction to Oceanography Memorial Day holiday Monday no lab meetings Go to any other lab section this week (and let the TA know!)

Mudskipper (Periophthalmus modestus) at low tide, photo by OpenCage, Wikimedia Commons, Creative Commons A S-A 2.5, http://commons.wikimedia.org/wiki/File:Periophthalmus_modestus.jpg

1 Tides Planet-length waves Cyclic, repeating rise & fall of sea level – Most regular phenomenon in the Daily tidal variation has great effects on life in & around the (Lab 8) Caused by gravity and between Earth, Moon & Sun, their orbits around each other, and the Earth’s daily spin

Photos by Samuel Wantman, Creative Commons A S-A 3.0, http://en.wikipedia.org/ wiki/File:Bay_of_Fundy_Low_Tide.jpg and http://en.wikipedia.org/wiki/ File:Bay_of_Fundy_High_Tide.jpg

Earth-Moon-Sun System

• Earth-Sun Distance 150,000,000 km

• Earth-Moon Distance 385,000 km Much closer to Earth, but much less massive • Earth Obliquity = 23.5 degrees – Seasons

Figure by Homonculus 2/Geologician, Wikimedia Commons, Creative Commons A 3.0, http://en.wikipedia.org/wiki/ File:Lunar_perturbation.jpg

2 Tides are caused by the gravity of the Moon and Sun acting on Earth and its ocean.

Pluto-Charon mutual orbit, Zhatt, Wikimedia Commons, Public Domain, http:// en.wikipedia.org/ wiki/File:Orbit2.gif

Newton’s cannon, Wikimedia Commons, Creative Commons A S-A 3.0, http://en.wikipedia.org/wiki/File:Newton_Cannon.svg • Basic Orbital Mechanics • Planetary objects stay in orbit due to balance of Gravity and Centrifugal forces (at their center of mass) • Like a weight spun on the end of string

Scaled image of Earth-Moon distance, Nickshanks, Wikimedia Commons, Creative Commons A 2.5

To Sun

Not to scale!

• Earth-Moon Distance Brews Ohare, Wikimedia, Public Domain, http://en.wikipedia.org/wiki/File:Earth- – 384,000 km Moon.PNG • Revolution period of the Moon – 27.3 Days • Rotation period of the Moon also 27.3 Days • Synchronous Rotation: We always see the same side of the Moon

3 Phases of the Moon • New Moon • Waxing Crescent • 1/2 Moon: First quarter WAXING CRESCENT • Full Moon First • Etc. Quarter – 7 days/quarter Full Moon

Third Quarter WANING CRESCENT Tom Ruen, Wikimedia Commons, Public Domain, http://en.wikipedia.org/wiki/ File:Moon_phase_calendar_ May2005.png

Phases of the Moon

1st Qtr

Full New

3rd Qtr

Figure from NASA Starchild, Public Domain), http://starchild.gsfc.nasa.gov/Images/StarChild/icons/ moon_above.gif

4 The Big Picture 3: Bulges

Figures from U. Tennessee, http://csep10.phys.utk.edu/astr161/lect/time/tides.html

• Moon’s gravitational force acting on the Earth tugs out a tidal bulge towards moon • Centrifugal force pushes a bulge away from moon on the far side of the Earth – TIDES TRY TO TRACK THE MOON

The Sun’s gravity has a similar, but smaller effect (1/2 as strong).

Andrew Buck, Wikimedia Commons, Creative Commons A S-A 3.0, http:// commons.wikimedia.org/wiki/File:Tidal_braking.svg

The Moon and Sun both influence tides

NOAA, Public Domain, http://oceanservice.noaa.gov/education/kits/tides/media/tide06a_450.gif Constructive interference: Sun and Moon tidal bulges oriented the same way, resulting in strong tides – Spring Tide

Destructive interference: Sun and Moon tidal bulges partially cancel each other, resulting in weak tides – Neap Tide

5 Effect of Sun & Moon Together • Spring Tides & Neap Tides

Adapted from figure by Nicky McLean, Wikimedia Commons, Public Domain, http://en.wikipedia.org/wiki/ File:Tide.Bridgeport.30d.png

Why is the moon’s effect on the tide greater than the sun’s? • Gravity balances Centrifugal at Earth’s center of mass • Elsewhere they don’t cancel – TIDE GENERATING FORCE:

GMMoon Ftides ∝ 3 REarth− Moon

• Tide generating force falls off faster with radius than gravity!

€

6 Equilibrium Theory of the Tides

Sun is much more massive! 7 » Msun ~ 3x10 Mmoon

BUT Sun is much further away!

» Rsun ~ 400 Rmoon

GMs 3 3 FS RSE Ms RmE 7 1 ≈ = 3 = 3×10 × 3 = 0.47 F GMm M R 400 L 3 m SE RmE

Solar tide 1/2 as big as lunar tide €

Tides in narrow, tapering bays • In narrow bays attached to the ocean, tides can slosh straight in and out • Large tides can occur when the tidal frequency matches natural (resonant) oscillations of the bay

Image from NOAA Online School for Weather, Public Domain, http:// www.srh.noaa.gov/ jetstream/ocean/ fundy_max.htm

7 Bay of Fundy tides

QUESTIONS?

Mont Saint-Michel and Tombelaine (tidal islands), France, Uwe Küchler, Wikimedia Commons, CC A S-A 3.0, http://commons.wikimedia.org/wiki/File:Mont_st_michel_aerial.jpg

8 Marine Life & Biological Productivity

Estimated marine chlorophyll & terrestrial vegetation coverage map 1997-1998, SeaWiFS/NASA, Public Domain, http://en.wikipedia.org/wiki/File:Seawifs_global_biosphere.jpg

CLASSIFICATION SCHEMES FOR MARINE ORGANISMS

1. Taxonomy: Based on genealogical relationships between organisms (ie, felines) 2. Mode of Nutrition 3. Habitat 4. Mobility

9 Genetic classification: Three Domains of Life 1. Bacteria: Simple single celled organisms, lack nucleus (E. coli) 2. Archaea: Outwardly similar to Bacteria; many live in extreme environments (hot springs, nuclear reactors, saline lakes, etc.) 3. Eucarya: Have a membrane-enclosed nucleus and other organelles; include protists, animals, fungi, plants

Whole genome tree of life, diagram by User_A1, based on Ciccarelli (2006) and Letunic (2007), Public Domain. http:// en.wikipedia.org/wiki/ File:CollapsedtreeLabels- simplified.svg

Bacteria Cyanobacterial colonies, left: NASA, Public Domain, http://microbes.arc.nasa.gov/images/content/gallery/lightms/ publication/lyngbya.jpg; right: Hamelin Pool -- Shark’s Bay, Australia, photo by Happy Little Nomad, Wikimedia commons, CC A S-A 2.0, http://en.wikipedia.org/wiki/File:Stromatolites_in_Shark_Bay.jpg

10 Archaea

Thermococcus Gammatolerans, an Archaebacterium, Halobacteria (actually Archaea) and Eukarya (Dunaliella Angels Tapias, Wikimedia Commons, Creative salina), San Francisco Bay CA, dro!d, Wikimedia Commons A 3.0 Unported, http:// Commons, Creative Commons A S-A 2.0 http:// commons.wikimedia.org/wiki/ commons.wikimedia.org/wiki/ File:Thermococcus_gammatolerans.jpg File:Salt_ponds_SF_Bay_%28dro!d%29.jpg

Eukaryota

Ostreococcus, a picoplankton (<1x10–6 m across!), Wenche Eikrem and Jahn Throndsen, University of Copepod, NOAA, Public OsloWikimedia Commons, CC A S-A Domain, http:// 2.5, http://en.wikipedia.org/wiki/ www.glerl.noaa.gov/pubs/ File:Ostreococcus_RCC143.jpg photogallery/Waterlife/ pages/0737.html

Public Domain

11 Questions?

Comb jelly(?) (Eukaryota), Nick Hobgood, Wikimedia Commons, Creative Commons A S-A 3.0, http://commons.wikimedia.org/wiki/File:Combjelly.jpg

What does it eat? 1. Autotrophs: Make their own food; Cyanobacteria, NASA, Public are the base of the food chain Domain, http:// microbes.arc.nasa.gov/images/ content/gallery/lightms/ a. Autotrophs are Primary Producers publication/lyngbya.jpg b. Photosynthesizing plants, algae, some bacteria (store solar energy) c. Chemosynthetic bacteria

Sargassum natans (eukarya), James St. John, Creative Commons Attribution 2.0 Generic, https:// commons.wikimedia.org/wiki/ File:Sargassum_natans_(brown_algae)_(San_Salvador_Is land,_Bahamas)_1_(15867880028).jpg

12 What does it eat? 1. Heterotrophs: cannot make their own food; must eat other organisms or their remains a. Herbivores: eat plants b. Carnivores: eat animals c. Omnivores: eat plants & animals d. Bacteria: many decompose dead organic matter (E. coli) Barracuda are heterotrophs, NOAA, Public Domain, http://www.photolib.noaa.gov/htmls/ reef2567.htm

So are yeast, Masur, Wikimedia Commons, Creative Commons A S-A 2.5, http://en.wikipedia.org/wiki/ File:S_cerevisiae_under_DIC_microscopy.jpg

Photosynthesis Living systems require chemical energy Chlorophyll: a green pigment that captures photons and transfers their energy to electrons, an through a series of steps creates carbohydrate molecules (chemical energy) and oxygen. Chlorophyll looks green because it absorbs red and blue light, and reflects green light Sargassum algae, NOAA, Public Domain, http://oceanexplorer.noaa.gov/ Adapted explorations/02sab/logs/aug09/media/ from figure lines.html by Aushulz, Wikimedia Commons, Creative Commons A S-A 3.0, http:// commons.wi kimedia.org/ wiki/ File:Chlorop hyll_ab_spe ctra2.PNG

13 Photosynthesis Reaction sunlight

6CO2 + 6H2O ——> C6H12O6 + 6O2 Carbon + water (yields) Glucose + Oxygen dioxide (a sugar)

Typically, ~100 grams carbon/ year / meter2 is fixed to sugar in the open ocean

PRIMARY PRODUCTION

• Amount of inorganic carbon (mainly

CO2) “fixed” by autotrophic organisms into organic compounds – Based on reactions harnessing solar or chemical energy

14 Respiration • Respiration: opposite reaction of photosynthesis • Dis-assembly of carbohydrate (food) molecules in the presence of oxygen to release chemical energy

• The main byproducts of respiration are H2O and CO2. These are released to the environment • Both plants & animals use respiration • Some bacteria & archea also respire + ENERGY

C6H12O6 + 6O2 ——> 6CO2 + 6H2O Glucose + Carbon (a sugar) Oxygen (yields) + water dioxide

Questions

Sargassum, photo from South Atlantic Fishery Management Council, http://www.safmc.net/Portals/6/weedline%202.jpg

15 How can we measure productivity?

-Timed weighing of autotrophs Good for big land plants, possible for large seaweed. However, measurements are only local. Hard to weigh microorganisms, particularly when they have a very short lifecycle. -Timed “weighing” of inorganic carbon

14 Add labeled inorganic carbon ( CO2) to ocean water See how fast organisms convert it to organic molecules Works well for microorganisms, but still a local measurement.

How can we measure productivity?

Color-imetry! (yes, it means what you think) - Chorophyll enables photosynthesis by absorbing blue and red light. Green light is reflected or scattered. - Green ocean implies lots of chlorophyll - Lots of chlorophyll implies lots of productivity! - Satellites like SEASTAR can measure color from space. This makes colorimetry ideal for global ocean surveys, if it works. This technique will be bad for long-lived plants (chlorophyll is present even when big plants aren’t active, I.e. spruce trees) HYPOTHESIS: Green color in the ocean correlates with primary productivity. PREDICTION: Productivity estimated from color should be the same as productivity measured by “weighing” uptake of inorganic carbon.

16 Colorimetry compared with “weighing” M.J. Behrenfeld & P.G. Falkowski. 1997. Photosynthetic rates derived from satellite-based chlorophyll concentration. Limnol. Oceanogr. 42:1-20

There is good agreement, but also a lot of scatter. Colorimetry may be a reasonable model, but we still Colorimetry

From Satellite Satellite From don’t know all the details!

From Measured uptake of inorganic 14C

Productivity from SeaWiFS

SeaWiFS/NASA/Rutgers University, Public Domain http://marine.rutgers.edu./opp/swf/Production/gif_files/PP_9809_9908.gif

17 Figure from University of Michigan, http://www.globalchange.umich.edu/ globalchange1/current/lectures/ kling/energyflow/typeeco2.gif

Primary Production 1. Amount depends on: a. Driving Energy (Solar or chemical) b. Nutrients 2. Regions of Highest Productivity a. Continental margins: Upwelling (Ekman pumping) and vertical mixing common along margins. Also close to rivers, dust sources b. Equatorial Divergences c. Antarctic Divergence d. Northern Pacific & Northern Atlantic i. Deepwater upwelling in Pacific; Divergence within subpolar Arctic/Atlantic gyres

18 Primary Production 3. Regions of Lowest Productivity a. Interiors of subtropical gyres i. This is where ocean water is most stably stratified --- Strong, stable , little vertical mixing. Few nutrients are brought up to the surface. --- These are the “deserts” of the ocean, most nutrients lost as dead organisms sink into the deep ocean

Primary Production 4. Primary Producers (Autrotrophs) a. Eukaryotic Algae (Seaweeds & Single celled photosynthesizers) i. Benthic (coastal): minor component i. Seaweeds ii. Pelagic : primary component i. Diatoms, dinoflagellates, coccolithophores, etc. b. Cyanobacteria: blue-green algae c. Picoplankton / Archea(?) d. Chemosynthetic Bacteria: Use inorganic compounds to get energy

i. They oxidize compounds such as H2S (Hydrogen sulfide)

19 Questions

Abalone, Oregon Coast Aquarium, photo by Little Mountain 5, Wikimedia Commons, Creative Commons A S-A 3.0, http:// commons.wikimedia.org/wiki/ File:Abalone_OCA.jpg

HABITAT

NOAA, Public Domain, http://oceanexplorer.noaa.gov/explorations/04deepscope/background/deeplight/media/diagram3_600.jpg

20 Ocean Habitats

• Where do organisms live in the oceans? – Biozones • Benthic vs. Pelagic – Sea floor vs. Free-floating/free-swimming

– Light Zones • Photic, Dysphotic, Aphotic

Habitat

1. Pelagic (oceanic): live in the water column 2. Benthic: Live in or on ocean bottom

Whale shark, Georgia aquarium, Zac Wolf, Creative Commons A S-A 2.5, http://commons.wikimedia.org/wiki/File:Whale-shark-enhanced.jpg

Coral polyp, Nick Hobgood, Creative Commons A S-A 3.0, http:// commons.wikimedia.org/wiki/ File:Euphyllia_glabrescens_%28Hard_coral%29_with_polyps_exte nded.jpg

21 Ocean Habitats

Figure by Chris_huh, Wikimedia Commons, Creative Commons A S-A 3.0, http://en.wikipedia.org/wiki/ File:Oceanic_divisions.svg

•Neritic vs. Oceanic –Shelf waters vs. deep waters –Neritic/Sublittoral: reaches to sea floor

Relative Habitat Sizes

• Abyssal pelagic: 54% oceans by volume • Abyssal: 75% sea floor by area

• Yet most of the bioproduction occurs elsewhere, near the surface

22 Questions

Spotted garden eel, photo by Nick Hobgood, Wikimedia Commons, Creative Commons A S- A 3.0, http://commons.wikimedia.org/wiki/ File:Heteroconger_hassi_%28Spotted_garden_ eel%29.jpg

Zonation by Lighting

• Photic Zone: lit by sunlight, ~ 100 - 500m deep – Euphotic Zone: autotrophs capture more energy than they use; net fixation of

carbon; net production of O2 – Dysphotic Zone: Not enough light for profitable photosynthesis • Aphotic Zone: Permanent darkness

23 Open Ocean

NOAA, Public Domain, http://oceanexplorer.noaa.gov/explorations/04deepscope/background/deeplight/media/diagram3_600.jpg

Coastal Ocean

NOAA, Public Domain, http://oceanexplorer.noaa.gov/explorations/04deepscope/background/deeplight/media/diagram3_600.jpg

24