DOCSLIB.ORG

Lunar Phases (Read the Following Lesson and Review Flashcards Before Doing Practice

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Lunar Phases (Read the Following Lesson and Review Flashcards Before Doing Practice Lunar Phases (Read the following Lesson and review Flashcards before doing Practice. You can also do th this on Study Island: 7 STEM.) Do as often as you wish. Phases of the Moon The changes in how much of the Moon's lit portion we can see from Earth are called the phases of the Moon. Because the Moon is revolving around the Earth, the amount of that lit portion we can see from Earth constantly changes. The Moon Reflects Light From the Sun The Moon's surface appears bright at least part of the time each month. This is because, as the Sun's light strikes the Moon's surface, the light is reflected onto the Earth where we can see it. The Moon does not make its own light. It reflects light from the Sun. The Moon's Phases The Sun shines on exactly one-half of the Moon, except during a lunar eclipse. From Earth, we can generally see only the part of the Moon that is lit by the Sun. The Moon's appearance changes over the period of about a month as the Moon moves in its orbit around the Earth. These changes give us the phases of the Moon. The time between one new Moon and the next is about 29½ days. When viewed from the Earth's surface, the main phases of the Moon look like the ones shown in the picture below. The eight Moon phases shown above are: 1. new moon 2. waxing crescent moon 3. first quarter moon 4. waxing gibbous moon 5. full moon 6. waning gibbous moon 7. third quarter moon 8. waning crescent moon If the Earth, Moon, and Sun were viewed from a point out in space, the phases of the Moon would look different from how they appear from the surface of the Earth. The diagrams below, which are not to scale, show how the Earth, Moon, and Sun are placed during each of the main Moon phases. Notice that the side of the Moon that is facing the Sun is always bright because it is receiving light, and the side of the Moon that faces away from the Sun is always dark because it does not receive any of the Sun's light. Moon Positions 1 Lunar Phases (Read the following Lesson and review Flashcards before doing Practice. You can also do th this on Study Island: 7 STEM.) Do as often as you wish. This diagram shows the different positions of the Moon. Moon Appearance from Earth This diagram shows the Moon's appearance from Earth. The numbered labels match the diagram that shows the different positions of the Moon. Between new Moon and full Moon, the Moon is waxing. This means that it appears to grow larger. Between full Moon and new Moon, the Moon is waning, which means it appears to grow smaller. 2 Lunar Phases (Read the following Lesson and review Flashcards before doing Practice. You can also do th this on Study Island: 7 STEM.) Do as often as you wish. th Lunar Phases 7 Grade Name ___________________ rd th Period 3 7 8th 1. The Sun always shines on half of the Moon. During a new moon, the Moon looks dark. Where is the lit side of the Moon during a new moon? A. The lit side faces toward the Earth. B. The lit side faces half away from the Earth. C. The lit side faces away from the Sun. D. The lit side faces away from the Earth. 2. The diagram below shows positions of the Moon as it orbits the Earth. Half of the Moon's surface is lit by sunlight no matter what the Moon's position. But the amount of the lit surface visible from Earth varies with the Moon's position. Examine the diagram below, and answer the question that follows. Which phase of the Moon is represented by position 6? A. waning crescent B. waning gibbous C. first quarter D. waxing gibbous 3. The table below shows the time that the Moon rose and set over a few days. Date Moon Rose Moon Set March 2 4:59 a.m. 2:16 p.m. March 3 5:38 a.m. 3:14 p.m. March 4 6:11 a.m. 4:14 p.m. Which of the following is the best prediction for the times that the Moon will rise and set on March 5? A. rise at 5:34 a.m., set at 3:18 p.m. B. rise at 7:42 a.m., set at 6:54 p.m. C. rise at 6:40 a.m., set at 5:14 p.m. D. rise at 6:20 a.m., set at 4:16 p.m. 3 Lunar Phases (Read the following Lesson and review Flashcards before doing Practice. You can also do th this on Study Island: 7 STEM.) Do as often as you wish. 4. The diagram below shows positions of the Moon as it orbits the Earth. Half of the Moon's surface is lit by sunlight no matter what the Moon's position. But the amount of the lit surface visible from Earth varies with the Moon's position. Examine the diagram below, and answer the question that follows. Which phase of the Moon is represented by position 7? A. first quarter B. waxing crescent C. waning crescent D. third quarter 5. The diagram below shows positions of the Moon as it orbits the Earth. Half of the Moon's surface is lit by sunlight no matter what the Moon's position. But the amount of the lit surface visible from Earth varies with the Moon's position. Examine the diagram below, and answer the question that follows. Which phase of the Moon is represented by position 6? A. waning crescent B. new Moon C. first quarter D. waning gibbous 6. The phases of the Moon are caused by the changing positions of the Earth and the Moon in relation to the Sun. Which items could best be used to represent the Sun, the Earth, and the Moon in a model that shows the phases of the Moon? 4 Lunar Phases (Read the following Lesson and review Flashcards before doing Practice. You can also do th this on Study Island: 7 STEM.) Do as often as you wish. A. an orange, a grapefruit, and a lime B. a flashlight, a basketball, and a softball C. a mirror, a fan, and some string D. a candle, a soccer ball, and a mirror 7. The diagram below shows positions of the Moon as it orbits the Earth. Half of the Moon's surface is lit by sunlight no matter what the Moon's position. But the amount of the lit surface visible from Earth varies with the Moon's position. Examine the diagram below, and answer the question that follows. Which phase of the Moon is represented by position 8? A. waxing crescent B. waning crescent C. full Moon D. third quarter 8. The diagram below shows positions of the Moon as it orbits the Earth. Half of the Moon's surface is lit by sunlight no matter what the Moon's position. But the amount of the lit surface visible from Earth varies with the Moon's position. Examine the diagram below, and answer the question that follows. Which phase of the Moon is represented by position 6? A. waning gibbous 5 Lunar Phases (Read the following Lesson and review Flashcards before doing Practice. You can also do th this on Study Island: 7 STEM.) Do as often as you wish. B. waxing crescent C. waxing gibbous D. first quarter 9. The diagram below shows positions of the Moon as it orbits the Earth. Half of the Moon's surface is lit by sunlight no matter what the Moon's position. But the amount of the lit surface visible from Earth varies with the Moon's position. Examine the diagram below, and answer the question that follows. Which phase of the Moon is represented by position 6? A. waxing gibbous B. full Moon C. waxing crescent D. waning gibbous 10. Ana is modeling the orbit of the Moon. The light bulb represents the Sun, the large ball represents Earth, and the small ball represents the Moon. Ana moved the small ball counter-clockwise, in the direction of the arrow. 6 Lunar Phases (Read the following Lesson and review Flashcards before doing Practice. You can also do th this on Study Island: 7 STEM.) Do as often as you wish. Based on the diagram of her model, what is the the phase of the Moon that people on Earth would see? First quarter, because people on Earth can see a quarter of the Moon illuminated and the Moon had just moved from the new moon A. position. B. New moon, because half of the Moon's surface is illuminated, so people on Earth will see that the entire Moon looks dark. Third quarter, because people on Earth can see a quarter of the Moon illuminated and the Moon had just moved from the full moon C. position. D. Full moon, because half of the Moon's surface is illuminated, so people on Earth will see the Moon's shape as a full circle. 11. The Moon orbits the Earth once in about _______. A. 365 days B. 28 days C. 24 hours D. 7 days 12. What event happens about once every month? A. a revolution of the Earth around the Sun B. a lunar eclipse C. a rotation of the Earth D.
Load more

Recommended publications
  • Orbit and Spin
    Orbit and Spin Overview: A whole-body activity that explores the relative sizes, distances, orbit, and spin of the Sun, Earth, and Moon. Target Grade Level: 3-5 Estimated Duration: 2 40-minute sessions Learning Goals: Students will be able to… • compare the relative sizes of the Earth, Moon, and Sun. • contrast the distance between the Earth and Moon to the distance between the Earth and Sun. • differentiate between the motions of orbit and spin. • demonstrate the spins of the Earth and the Moon, as well as the orbits of the Earth around the Sun, and the Moon around the Earth. Standards Addressed: Benchmarks (AAAS, 1993) The Physical Setting, 4A: The Universe, 4B: The Earth National Science Education Standards (NRC, 1996) Physical Science, Standard B: Position and motion of objects Earth and Space Science, Standard D: Objects in the sky, Changes in Earth and sky Table of Contents: Background Page 1 Materials and Procedure 5 What I Learned… Science Journal Page 14 Earth Picture 15 Sun Picture 16 Moon Picture 17 Earth Spin Demonstration 18 Moon Orbit Demonstration 19 Extensions and Adaptations 21 Standards Addressed, detailed 22 Background: Sun The Sun is the center of our Solar System, both literally—as all of the planets orbit around it, and figuratively—as its rays warm our planet and sustain life as we know it. The Sun is very hot compared to temperatures we usually encounter. Its mean surface temperature is about 9980° Fahrenheit (5800 Kelvin) and its interior temperature is as high as about 28 million° F (15,500,000 Kelvin).
    [Show full text]
  • GCSE Astronomy Course Sample N Section 3 Topic 2 N the Moon’S Orbit
    Sample of the GCSE Astronomy Course from Section 3 Topic 2 The Moon’s orbit Introduction We can see that the Moon changes its appearance by the day. In this topic you will study the orbit of the Moon and the changes that this brings about. You will learn about the phases of the Moon, why you can only see one side of the Moon from Earth, and what gives rise to our ability to see a small fraction of the far side. You will probably need 2 hours to complete this topic. Objectives When you have completed this topic you will be able to: n explain the rotation and revolution (orbit) of the Moon n describe the phases of the lunar cycle n explain the synchronous nature of the Moon’s orbit and rotation n explain the causes of lunar libration and its effect on the visibility of the lunar disc. Rotation and orbit of the Moon The Moon rotates about its axis in 27.3 days. The Moon orbits round the Earth in a period which is also 27.3 days. This means that we only see one side of the Moon (around 59 per cent of the lunar disc). The axis of the Moon has a slight tilt. The Moon’s equator is tilted by 1.5° to the plane of its orbit around the Earth. You may recall from Section 2 that the plane in which the Earth orbits the Sun is called the ecliptic. The plane of the Moon’s orbit is 5.1° to the ecliptic and the orbit is elliptical.
    [Show full text]
  • Pdf [35] Ghoddousi-Fard, R
    International Journal of Astronomy and Astrophysics, 2021, 11, 343-369 https://www.scirp.org/journal/ijaa ISSN Online: 2161-4725 ISSN Print: 2161-4717 Updating the Historical Perspective of the Interaction of Gravitational Field and Orbit in Sun-Planet-Moon System Yin Zhu Agriculture Department of Hubei Province, Wuhan, China How to cite this paper: Zhu, Y. (2021) Abstract Updating the Historical Perspective of the Interaction of Gravitational Field and Orbit Studying the two famous old problems that why the moon can move around in Sun-Planet-Moon System. International the Sun and why the orbit of the Moon around the Earth cannot be broken Journal of Astronomy and Astrophysics, = 2 11, 343-369. off by the Sun under the condition calculating with F GMm R , the at- https://doi.org/10.4236/ijaa.2021.113016 tractive force of the Sun on the Moon is almost 2.2 times that of the Earth, we found that the planet and moon are unified as one single gravitational unit Received: May 17, 2021 2 Accepted: July 20, 2021 which results in that the Sun cannot have the force of F= GMm R on the Published: July 23, 2021 moon. The moon is moved by the gravitational unit orbiting around the Sun. It could indicate that the gravitational field of the moon is limited inside the Copyright © 2021 by author(s) and Scientific Research Publishing Inc. unit and the gravitational fields of both the planet and moon are unified as This work is licensed under the Creative one single field interacting with the Sun.
    [Show full text]
  • Moon-Earth-Sun: the Oldest Three-Body Problem
    Moon-Earth-Sun: The oldest three-body problem Martin C. Gutzwiller IBM Research Center, Yorktown Heights, New York 10598 The daily motion of the Moon through the sky has many unusual features that a careful observer can discover without the help of instruments. The three different frequencies for the three degrees of freedom have been known very accurately for 3000 years, and the geometric explanation of the Greek astronomers was basically correct. Whereas Kepler’s laws are sufficient for describing the motion of the planets around the Sun, even the most obvious facts about the lunar motion cannot be understood without the gravitational attraction of both the Earth and the Sun. Newton discussed this problem at great length, and with mixed success; it was the only testing ground for his Universal Gravitation. This background for today’s many-body theory is discussed in some detail because all the guiding principles for our understanding can be traced to the earliest developments of astronomy. They are the oldest results of scientific inquiry, and they were the first ones to be confirmed by the great physicist-mathematicians of the 18th century. By a variety of methods, Laplace was able to claim complete agreement of celestial mechanics with the astronomical observations. Lagrange initiated a new trend wherein the mathematical problems of mechanics could all be solved by the same uniform process; canonical transformations eventually won the field. They were used for the first time on a large scale by Delaunay to find the ultimate solution of the lunar problem by perturbing the solution of the two-body Earth-Moon problem.
    [Show full text]
  • Effects of the Moon on the Earth in the Past, Present, and Future
    Effects of the Moon on the Earth in the Past, Present, and Future Rina Rast*, Sarah Finney, Lucas Cheng, Joland Schmidt, Kessa Gerein, & Alexandra Miller† Abstract The Moon has fascinated human civilization for millennia. Exploration of the lunar surface played a pioneering role in space exploration, epitomizing the heights to which modern science could bring mankind. In the decades since then, human interest in the Moon has dwindled. Despite this fact, the Moon continues to affect the Earth in ways that seldom receive adequate recognition. This paper examines the ways in which our natural satellite is responsible for the tides, and also produces a stabilizing effect on Earth’s rotational axis. In addition, phenomena such as lunar phases, eclipses and lunar libration will be explained. While investigating the Moon’s effects on the Earth in the past and present, it is hoped that human interest in it will be revitalized as it continues to shape life on our blue planet. Keywords: Moon, Earth, tides, Earth’s axis, lunar phases, eclipses, seasons, lunar libration Introduction lunar phases, eclipses and libration. In recognizing and propagating these effects, the goal of this study is to rekindle the fascination humans once held for the Moon Decades have come and gone since humans’ fascination and space exploration in general. with the Moon galvanized exploration of the galaxy and observation of distant stars. During the Space Race of the 1950s and 1960s, nations strived and succeeded in reaching Four Prominent Lunar Effects on Earth Earth’s natural satellite to propel mankind to new heights. Although this interest has dwindled and humans have Effect on Oceans and Tides largely distanced themselves from the Moon’s relevance, its effects on Earth remain as far-reaching as ever.
    [Show full text]
  • Analytical Formulation of Lunar Cratering Asymmetries Nan Wang (王楠) and Ji-Lin Zhou (周济林)
    A&A 594, A52 (2016) Astronomy DOI: 10.1051/0004-6361/201628598 & c ESO 2016 Astrophysics Analytical formulation of lunar cratering asymmetries Nan Wang (王`) and Ji-Lin Zhou (hN林) School of Astronomy and Space Science and Key Laboratory of Modern Astronomy and Astrophysics in Ministry of Education, Nanjing University, 210046 Nanjing, PR China e-mail: [email protected] Received 28 March 2016 / Accepted 3 July 2016 ABSTRACT Context. The cratering asymmetry of a bombarded satellite is related to both its orbit and impactors. The inner solar system im- pactor populations, that is, the main-belt asteroids (MBAs) and the near-Earth objects (NEOs), have dominated during the late heavy bombardment (LHB) and ever since, respectively. Aims. We formulate the lunar cratering distribution and verify the cratering asymmetries generated by the MBAs as well as the NEOs. Methods. Based on a planar model that excludes the terrestrial and lunar gravitations on the impactors and assuming the impactor encounter speed with Earth venc is higher than the lunar orbital speed vM, we rigorously integrated the lunar cratering distribution, and derived its approximation to the first order of vM=venc. Numerical simulations of lunar bombardment by the MBAs during the LHB were performed with an Earth–Moon distance aM = 20−60 Earth radii in five cases. Results. The analytical model directly proves the existence of a leading/trailing asymmetry and the absence of near/far asymmetry. The approximate form of the leading/trailing asymmetry is (1+A1 cos β), which decreases as the apex distance β increases. The numer- ical simulations show evidence of a pole/equator asymmetry as well as the leading/trailing asymmetry, and the former is empirically described as (1 + A2 cos 2'), which decreases as the latitude modulus j'j increases.
    [Show full text]
  • Lab # 3: Phases of the Moon
    Name(s): Date: 3 Phases of the Moon 3.1 Introduction Every once in a while, your teacher or TA is confronted by a student with the question “Why can I see the Moon today, is something wrong?”. Surprisingly, many students have never noticed that the Moon is visible in the daytime. The reason they are surprised is that it confronts their notion that the shadow of the Earth is the cause of the phases–it is obvious to them that the Earth cannot be causing the shadow if the Moon, Sun and Earth are simultaneously in view! Maybe you have a similar idea. You are not alone, surveys of science knowledge show that the idea that the shadow of the Earth causes lunar phases is one of the most common misconceptions among the general public. Today, you will learn why the Moon has phases, the names of these phases, and the time of day when these phases are visible. Even though they adhered to a “geocentric” (Earth-centered) view of the Universe, it may surprise you to learn that the ancient Greeks completely understood why the Moon has phases. In fact, they noticed during lunar eclipses (when the Moon does pass through the Earth’s shadow) that the shadow was curved, and that the Earth, like the Moon, must be spherical. The notion that Columbus feared he would fall of the edge of the flat Earth is pure fantasy—it was not a flat Earth that was the issue of the time, but how big the Earth actually was that made Columbus’ voyage uncertain.
    [Show full text]
  • Lunar Standstills and Chimney Rock
    Lunar Standstills and Chimney Rock Thomas Hockey To understand the motion of something, we require a reference. For a car, it’s the road. For the hands of a clock, it’s the numbered dial behind them. In the case of the Moon seen in the sky, nature provides a terrific reference: It’s the background of stars. The stars are so distant that their motions through space are imperceptible to the naked eye over human history. Thus we speak of the “fixed stars.” Imagine that the spherical Earth is surrounded by a shell of fixed stars. It isn’t really, of course. (The stars are at varying distances from the Earth, they aren’t physically attached to anything, etc.) Still, that’s what it looks like! During the course of the night, this shell appears to partly rotate around us, due to the Earth—the thing that’s really rotating—turning completely once each twenty-four-hour day. You can even infer the place in the sky about which the shell seems to be spinning. It’s a point, directly north, about one third of the way from the horizon at Chimney Rock to the point overhead. Look for the star of modest brightness (the “North Star”) that nearly marks its exact location. This North Celestial Pole [NCP] is just the extension of the Earth’s North Pole (one of two poles defining the axis about which the Earth rotates), infinitely into the sky. (The South Celestial Pole [SCP] is forever below the southern horizon at Chimney Rock.) We can do better than just imagining! A few hours spent stargazing under the real sky will convince you that this is true.
    [Show full text]
  • 1 Sam Bell the Moon Darby Dyar Schmitt (1991) Schmitt (1991
    Sam Bell The Moon Darby Dyar Schmitt (1991) Schmitt (1991) presents in a very comprehensive and clear way the history of lunar formation as known purely from the Apollo and Luna results. While he definitely succeeds at this, there are two places where he disagrees with modern theories of the Moon without presenting the main evidence for those theories (which does not come from Apollo results). But it is definitely a very good paper overall. The bulk of the paper consists of Schmitt breaking lunar history into seven sections: In the first section, he claims that the Moon formed by coaccretion with the Earth (in contrast to the now-dominant impact hypothesis). The next section is the lunar magma ocean phase, where an ocean of silicate rock of ultramafic composition covered the Moon. Lighter elements floating to the top of the magma ocean formed a crust of ferroan anorthosite (pure CaAl2Si2O8 with small amounts of iron), and heavier crystals sinking to the bottom of the ocean formed an ultramafic mantle. The last layer to crystallize is known by the acronym KREEP because it became enriched in potassium, rare earth elements, and phosphorus. The third stage that Schmitt (1991) picks out is a period from roughly 4.4Ga to roughly 4.2Ga, when the anorthosite crust was saturated with early craters. The next stage lasts until roughly 3.9Ga and consists of the formation of the oldest large impact basins and the crystallizing of the KREEP fluid layer. Some of the KREEP is thought to have intruded into the anorthosite crust.
    [Show full text]
  • Geochemical Constraints on the Origin of the Moon and Preservation of Ancient Terrestrial Heterogeneities
    S. J. Lock et al., Space Science Reviews, 216, 109, doi: 10.1007/s11214-020-00729-z, 2020 Geochemical constraints on the origin of the Moon and preservation of ancient terrestrial heterogeneities Simon J. Locka,∗, Katherine R. Berminghamb,c, Rita Paraid, Maud Boyete aDivision of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125, USA. bDepartment of Earth and Planetary Sciences, Rutgers University, Piscataway, NJ 08854, USA cDepartment of Geology, University of Maryland,College Park, MD 20742, USA. dDepartment of Earth and Planetary Sciences, Washington University in St. Louis, Saint Louis, MO 63130, USA. eUniversit´eClermont Auvergne, CNRS, IRD, OPGC, Laboratoire Magmas et Volcans, F-63000 Clermont-Ferrand, France. Abstract The Moon forming giant impact marks the end of the main stage of Earth's accretion and sets the stage for the subsequent evolution of our planet. The giant impact theory has been the accepted model of lunar origin for 40 years, but the parameters of the impact and the mechanisms that led to the formation of the Moon are still hotly debated. Here we review the principal geochemical observations that constrain the timing and parameters of the impact, the mechanisms of lunar formation, and the contemporaneous evolution of Earth. We discuss how chemical and isotopic studies on lunar, terrestrial and meteorite samples relate to physical models and how they can be used to differentiate between lunar origin models. In particular, we argue that the efficiency of mixing during the collision is a key test of giant impact models. A high degree of intra-impact mixing is required to explain the isotopic similarity between the Earth and Moon but, at the same time, the impact did not homogenize the whole terrestrial mantle, as isotopic signatures of pre-impact heterogeneity are preserved.
    [Show full text]
  • Educator's Resource Guide
    EDUCATOR’S RESOURCE GUIDE TAKE YOUr students for a walk on the moon. Table of Contents Letter to Educators . .3 Education and The IMAX Experience® . .4 Educator’s Guide to Student Activities . .5 Additional Extension Activities . .9 Student Activities Moon Myths vs. Realities . .10 Phases of the Moon . .11 Craters and Canyons . .12 Moon Mass . .13 Working for NASA . .14 Living in Space Q&A . .16 Moonology: The Geology of the Moon (Rocks) . .17 Moonology: The Geology of the Moon (Soil) . .18 Moon Map . .19 The Future of Lunar Exploration . .20 Apollo Missions Quick-Facts Reference Sheet . .21 Moon and Apollo Mission Trivia . .22 Space Glossary and Resources . .23 Dear Educator, Thank you for choosing to enrich your students’ learning experiences by supplementing your science, math, ® history and language arts curriculums with an IMAX film. Since inception, The IMAX Corporation has shown its commitment to education by producing learning-based films and providing complementary resources for teachers, such as this Educator’s Resource Guide. For many, the dream of flying to the Moon begins at a young age, and continues far into adulthood. Although space travel is not possible for most people, IMAX provides viewers their own unique opportunity to journey to the Moon through the film, Magnificent Desolation: Walking on the Moon. USING THIS GUIDE This thrilling IMAX film puts the audience right alongside the astronauts of the Apollo space missions and transports them to the Moon to experience the first This Comprehensive Educator’s Resource steps on the lunar surface and the continued adventure throughout the Moon Guide includes an Educator’s Guide to Student missions.
    [Show full text]
  • Foreseechange Pty Ltd Acn 094 521 614
    foreseechange forecasting and futures consultants foreseechange pty ltd acn 094 521 614 11 August 2009 Supplementary Submission No. 23-1 to the House of Representatives Industry, Science and Innovation Committee enquiry into long-term meteorological forecasting in Australia: Supplementary Submission This supplementary submission documents the additional research undertaken since the original submission on 22 April 2009. In my original submission, I documented my finding that rainfall in Melbourne and the Murray Darling Basin is quite strongly influenced by the 18.6 year lunar node cycle. Discussions I have had with researchers since then indicate that this not a factor which has been or is being considered as a driver of rainfall cycles – despite my finding that this is a major driver and that it is predictable with a high degree of accuracy long into the future. Since my original submission, I have now quantified the impact of another major influence on rainfall in Melbourne and the Murray Darling Basin. This is the Indian Ocean dipole and this submission extends the previous document to include the results of this analysis. This is a factor which explains large annual variations in rainfall. It is only a partial explanation of the intensification of the drought since 2005 and so the search for another factor must continue. The lunar node cycle forces decadal variations in rainfall while the Indian Ocean dipole influences annual rainfall variations. Understanding the combined effect of these two factors (and others) opens up the potential for both improved seasonal rainfall forecasting and longer-term rainfall forecasting. I have also edited some of the previous charts to better reflect the impact of the lunar node cycle.
    [Show full text]