ENHANCING MASTERY OF EARTH SCIENCE CONCEPT OF PROSPECTIVE PHYSICS TEACHERS THROUGH INTERACTIVE CONCEPTUAL INSTRUCTION SUPPORTED BY VISUALIZATION AND GRADS

Most all of earth and space science concepts are unobservable and require reasoning. Unobservable concepts have made prospective physics teachers found it hard to understand the concepts correctly. It needs visualization to help understand the concepts easily. The aim of this study was to enhance the mastery concept of earth science topic especially the earth atmosphere using interactive conceptual with visualizations and authentic data analysis with GrADS (Grid Analysis Display System). There were 23 prospective physics teachers in Bengkulu, Indonesia participated in this study. A convenience sampling technique was employed in this study. This study used pre-experimental, one group pretest-posttest design. The data were collected using pretest and posttest, questionnaires, and observation sheets. The pretest and posttest were analyzed quantitatively, while the questionnaires were analyzed qualitatively. The results showed that the prospective physics teachers’ concept mastery improved from no mastery to compete with the average normalized gain of 0.64 (medium category). 30.44% of the prospective physics teachers obtained the N-gain score in the high category and 69.56% obtained the N-gain score in the moderate category. This compilation gave them experience about the real condition of solar radiation in Indonesian atmosphere during their learning activity. It concluded that the earth science learning using interactive conceptual instruction supported by visualization and GrADS could enhance the students’ concept mastery. © 2018 Science Education Study Program FMIPA UNNES Semarang


INTRODUCTION
Utmost of earth atmosphere phenomena are indirectly observable which require favorable reasoning to understand.Therefore, media assistance are needed to explain the earth atmosphere concepts due to visualize the imaginary, abstract concepts (Bilici et al., 2011;Park, 2013;Sunderlin, 2009).It was also reinforced by the previous investigation that about 78% of the future science teachers considered that geoscience materials were fairly convoluted and abstract which therefore made them difficult to understand (Rosnita, 2016;Miller & Brewer, 2010).Hence, a neatlyconstructed learning on earth atmosphere should be designed in order to assist future science teach-ers to improve their concept mastery (Jolley et al., 2012).A research carried out in Bengkulu using the Search, Solve, Create, and Share (SSCS) learning model indicated a slight enhancement of mastery concept having the N-Gain score of 0.49 and belonged to the 'moderate' category (Johan et al., 2018a).The Interactive Conceptual Interaction (ICI) applied in this research focused on evocative learning aiming at improving the future science teachers' mastery of earth and space concepts.Moreover, this study provided the established ICI model supported by authentic data of atmospheric phenomena as the main materials.
One of the ways to advance the concept mastery is by using a scientific model to aid learners in comprehending the concepts (King, 2010;Park, 2013;Sibley, 2009;Saribas et al., 2016).According to Bloom, notion mastery is the capability to comprehend the substance of learning expansively, and be able to offer clarification, as well as apply it (Anderson, 2010).Mastery concept is the fundamental aspect of learning, and the use of technology has proven to overcome the obstacles as the harnessing of science has become an educational research trend.Smith & Bermea (2012) applied the sketching technique as the alternative conception of the plate tectonics.However, media visualization has not been commonly used in Bengkulu particularly on the earth and space topic.Furthermore, previous studies have shown the improvement of earth and science concepts through the use of sketching, visualization, and animation techniques (Prain et al., 2009;Smith & Bermea, 2012;Samsudin et al., 2016;Kali & Linn, 2008).Other than that, analogies, real replicas or diagram were also utilized in some research to advance future science teachers' concept mastery (Jee et al., 2010;Sibley, 2009;Passmore et al., 2014).In other words, technology has facilitated the interpretation of abstract, unobservable concepts such as earth and space.In this case, the animation is most-adapted technology to help students catch a proper understanding of such concepts.Profound comprehension of the connection between scientific independence, technology, and pro-environmental behaviors are necessary for students to support them in various courses (Bezen et al., 2016;Santos & Arroio, 2016;Kastens, 2010).
Geoscience visual representation could aid students for the betterment of their understanding.This research presented multi modus visualization such as animation, graphs, and figures which configured each other to ease the students in comprehending the concepts.The visualization of this research emerged as the results of authen-tic data analysis with GrADS, which has never been done before.In addition, the results of this research could be later used to support students' thinking process as well as give varying learning experience.The authentic data were computed using the Matrix Laboratory (MATLAB) to produce 3-Dimension visualization (Werts & Hinnov, 2011;Ellwein et al., 2014) while the Indonesian atmospheric data were analyzed using the Grid Analysis Display System (GrADS).In addition, a module was developed referring to the authentic data.
Captivating students' attention to interpreting the GrADS data visualization would be a remarkable learning experience which was expected to result in the improvement of earth and space concept mastery.Making use of the GrADS system in a learning process particularly on the earth and science topic has not been published yet.The GrADS and MATLAB results were approximately indistinguishable yet the GrADS was fairer to be used than the MATLAB.
With this in mind, the researchers frankly said that this research intended to enhance the earth science concept mastery of the future physics teachers for the analysis level especially the earth atmosphere employing the interactive conceptual instruction with the aid of GrADS and visualization.

METHODS
Pre-experimental research was conducted with one group pretest-posttest research design.23 prospective physics teachers were involved in this study.There were three stages of research including pre-implementation, implementation of one group pre-test post-test design, and postimplementation.In the pre-implementation, kinds of media for visualization to every concept were recognized qualitatively to advance prospective physics teachers' concept mastery.
The studied materials included the composition of air mass, atmospheric pressure, atmospheric temperature, the ozone layer, and ıncoming solar radiation.In this stage, the learning activities using the ICI model and data collection tools were created.There were four stages in the learning; the focus of concept, textbook usage, interactive classroom, research-based materials.The research-based materials were the results of the GrADS authentic data analysis which measured the net solar radiation in January-December 1990.The output of the GrADS was the display of Indonesian atmosphere actual condition.These visualizations intended to assist the fu-ture physics teachers to understand the concepts.
In the implementation step, the ICI was run to 23 future physics teachers in Bengkulu, Indonesia.The participant had never joined the Earth and Space course before.These participants were chosen by using the Convenience Sampling technique.The data of prospective physics teachers' mastery were obtained from the pretest and posttest.The mastery differences found in the pretest and posttest score were then computed as the N-Gain <g> (Hake in Jackson et al., 2008).
Description: S pre = pretest score; S post = posttest score; S max =maximum score Some instruments were needed in this research to collect the data.The quantitative data of concept mastery were collected through multiple choice questions while the qualitative data of prospective physics teachers' responses were collected through open-ended questions.The instruments employed were authenticated by a proficient team.There were four professionals partook in authenticating the instruments.The instruments used in this research were verified by 34 prospective physics teachers.Based on the experts and instrument implementation, it concluded that the research' instruments were valid and reliable.The sample of question is as follows: "Based on the graph of annual solar movement, the incoming solar radiation on 23,5 o of the northern hemisphere at summer solstice is…." (Note: BBS is southern hemisphere; BBU is northern hemisphere; 0 o is equator).
The classroom activities carried out in this lesson are presented in Table 1 In the pre-implementation stage, the type visualization was qualitatively examined for each concept.The visualizations were in the form of animations, figure, graphs, and GrADS picturization.The examination of visualization type was to ensure that the students have had an appropriate understanding to avoid misunderstanding, also, advance their thinking skills.These kinds of visualization were then adopted to the developed learning program.

RESULTS AND DISCUSSION
This research aimed to describe the enhancement of prospective physics teachers' concept mastery known from the differences between the post-test and pre-test results.The students' early knowledge was known through the pre-test and the increase was examined through the post-test.The below Table informs the   Table 2 provides the dissimilar between the correct answers at pre-test and post-test for each concept; also, the improvement of pre-service physics teachers' mastery.The Bloom's revised taxonomy stages were adopted.The influence of the learning process was specified on the enhancement of mastery aspects (C2).Based on data displayed in Table 2, there was a shift in the students' mastery concept seen from the high increase of atmospheric pressure, atmospheric temperature, and incoming solar radiation mastery.Furthermore, there was 52.1% of correct answers on the pre-test for atmospheric temperature materials and 100% of correct answers on the post-test.This made it the highest improvement among others.On the other hand, there was only 13% of correct answers on the pre-test for air mass composition and was increased by 17.5% to become 30.5% on the post-test.However, the lowest increased was on the analysis (C4) of the ozone layer which scored an improvement of 17.3% although the other C4 of incoming solar radiation scored high (47.9%).
Table 3 informs the enhancement distribution of concept mastery on each N-Gain level.A student's concept mastery was calculated from each student's understanding of all concepts.The data of the students' increase in all concept mas-tery elucidated that no one had low concept mastery and all of them categorized as the medium as the N-Gain average score was 0.69.It appears in Table 3 that 30.44% of future physics teachers were in the high category and other 69.56% of them were in the medium category.
Those remarkable improvements emerged as a result of the use of various visualization types.It seems that different type of visualization has a different impact.The learning of air mass composition, which scored the least, used tables and graphs.A distinct difference between the two C4 aspects was quite interesting.The C4 of incoming solar radiation, which scored higher, utilized the combination of animation and GrADS visualization.Supposedly, this compilation influenced their concept mastery in analysis level as it helped the students to understand the concepts easily and clearly.Furthermore, Table 3 shows that most students are in the high and medium category based on the N-gain for concept mastery.The use of visualization media was closely related these pleasant results since it enabled students to watch the unobservable phenomena of Earth and Space especially the atmospheric.This was supported by the results of the questionnaires which revealed that most students considered media visualization, especially animation, as the most helpful aid.
The display of the GrADS output by analyzing the authentic data has given an expressive effect for the research.The findings indicated that the learning processes supported by researchbased materials had the advantage of being able to describe the actual condition of nature.The display of the GrADS output by analyzing the authentic data of real solar radiation in 1990 is presented in Figure 1.The above visualizations are the analysis results of surface net solar radiation from GrADS which is influenced by latitude and position during annual solar movement.The incoming solar radiation influences temperature and pressure in the atmosphere while the colors indicate the different amount of solar radiation.For instance, the northern hemisphere has surplus solar radiation on July and deficit of solar radiation in July 1990.Having such de-tails, this kind of visualization could support learning the atmospheric pressure, atmospheric temperature, and incoming solar radiation concepts and the correlation between each concept.
After being provided the actual condition of Indonesia Solar Radiation, the students were asked to relate the net solar radiation and the sun's motion during the year, which is seen in Figure 2.  2a and 2b, the students could obviously notice the distribution of solar radiation in Indonesia both on the northern and southern hemisphere while Figure 2c shows the annual solar movement.Therefore, the students could easily draw conclusion why the northern hemisphere of Indonesia has surplus solar Radiation in June 1990.This is parallel with Mountney (2009) who stated that animation that used in learning gives dynamic situational of an object and this is potential to explore logic thinking.Moreover, the concepts of incoming solar radiation and atmospheric temperature, as well as its correlation, could also be explained.This is similar with previous research elucidating that visualization could explain the correlation among various variables (Werts & Hinnov, 2011).Therefore, it supports the opinion suggesting that the collaboration of visual media and authentic data in learning contributes to students' reasoning skills to reach the proper concept mastery (Johan et al., 2018a;Johan et al., 2018b).Improvement of mastery concept is also influenced by the learning process that stimulated student's curiosity and motivation.Similar research stated that virtual visualization as a game in learning activity could improve enthusiasm or interest in learning (Ismawati et al., 2014).Furthermore, this learning potentially enhances the spiritual aspect.It causes earth science learning helped by GrADS could display the real condition of the earth atmosphere (Johan et al., 2018a;Johan et al., 2018b).
The use of visualization to ease the concept understanding was agreed upon by the students through the questionnaires.Based on the students' responses to the questionnaires, it summed up that: (1) The Earth and Space learning using visualizations was more interesting; (2) The use of visualization, especially animation, has helped them to comprehend the atmospheric concepts easier; (3) The animation was very clear and able to help to simplify the concepts; (4) Animations made the learnings became more enjoyable.Visualizations are also able to foster curiosity and motivation.These learning results were also supported by previous research that stated multimedia teaching materials including text, graphics, images, audio, video, and animation gave more significant effect on students' cognitive (Khoiriah et al., 2016).Other research reported that motivation was important factors for successful learning activities (McConnell & Kraft, 2011;Lee & Pang, 2013).

CONCLUSION
Based on the above results and discussion, it concluded that the earth atmosphere learning through conceptual interactive using visualizations was the potential to improve prospective physics teachers' concept mastery.The prospective physics teachers' concept mastery improved quite remarkably and categorized as medium based on the average N-Gain score of 0.64.The visualization of solar radiation authentic data analyzed using the GrADS helped the students to understand the concept easier and gave them experience about the real Indonesia solar radiation.the improvement of prospective physics teachers' conceptual levels indicated that visualization made the learnings became more interesting and explored their thinking skills.Visualizations give the concept details plainly and showed the relationship of various variables or concepts in the earth atmospheric phenomena.It is expected for future research to exploit other phenomena to be displayed in classes for the betterment of preservice physics teachers' quality.
pre-and post-test of the students.The focus of concept: Picturizations as to help comkeep up with the latest terms, or keywords of the visualized concepts Research-based materials: The output of the GrADS program which displays the actual Indonesian atmosphere used to support the students to comprehend the notion

Figure 2 .
Figure 2. (a) and (b).The Surface Net Solar Radiation in Indonesia's Atmosphere on March and September 1990; (c).The Annual Solar MovementThe Figure2a, 2b, and 2c are correlated with each other.Based on Figure2aand 2b, the students could obviously notice the distribution of solar radiation in Indonesia both on the northern and southern hemisphere while Figure2cshows the annual solar movement.Therefore, the students could easily draw conclusion why the northern hemisphere of Indonesia has surplus solar Radiation in June 1990.This is parallel withMountney (2009) who stated that animation that used in learning gives dynamic situational of an object and this is potential to explore logic thinking.Moreover, the concepts of incoming solar radiation and atmospheric temperature, as well as its correlation, could also be explained.This is similar with previous research elucidating that visualization could explain the correlation among various variables(Werts & Hinnov, 2011).Therefore, it supports the opinion suggesting that the collaboration of visual media and authentic data in learning contributes to students' reasoning skills to reach the proper concept mastery(Johan et al., 2018a; Johan et al., 2018b).Improvement of mastery concept is also influenced by the learning process that stimulated student's curiosity and motivation.Similar research stated that virtual visualization as a game in learning activity could improve enthusiasm or interest in learning(Ismawati et al., 2014).Furthermore, this learning potentially enhances the spiritual aspect.It causes earth science learning helped by

Table 1 .
The Classroom Activities

Table 2 .
The Data of Correct Answer at Pre-Test and Post-Test

Table 3 .
The Distribution of N-gain Figure 1.The GrADS Output Displaying Actual Condition of Indonesia Solar Radiation on the Atmosphere in March, July, September, and November 1990