The Analysis of Global Warming Patterns from 1970s to 2010s

While global warming is only one part of climate change effects, it poses the highest risk to our habitats and ecologies. It is alarming that global warming has heightened in multiple locations and is intensified since the early 1970s. Since then, there are certain global warming patterns that could guide us with an overview of what mitigation and adaptation strategies should be developed in the future decades. There are certain regions affected more than another, and there are certain patterns with adverse effects on regions, sub-regions, and even continents. This study provides an insightful analysis of recent global warming patterns, those that are affecting us the most with regional climate change of different types, upsurge in frequency and intensity of natural disasters, and drastic impacts on our ecosystems around the world. By analysing the global warming patterns of these last four decades, this research study sheds light on where these patterns are coming from, how they are developing, and what are their impacts. This study is conducted through grey literature and analysis of the recorded global warming data publicly available by the NASA-GISS data centre for global temperature. This brief—but com-prehensive—analysis helps us to have a better understanding of what comes next for global warming impacts, and how we should ultimately react. The study contributes to the field by discovering three key points analysed based on available data and literature on recorded global temperature, including: differences between north and south hemispheres, specific patterns due to ocean surface temperature increase, and recent impacts on particular regions. The study concludes with the importance of global scale analysis to have a more realistic understanding of the global warming patterns and their impacts on all living habitats.


Introduction
Global warming is one of the primary effects of climate change [1] [2]. The existing scholarly studies prove the gradual increase since the mid-19th century [3] [4] [5] [6] [7]. The regional warming studies also indicate the increasing temperature in particular locations and larger scales that include both natural and built habitats [8] [9] [10] [11]. Hence, many context-specific studies have recorded significant impacts on productivity [12], frequency and intensity of natural disasters [2] [13] [14] [15], the reoccurrence and severity of natural disasters [16], surface warming [17], water shortage [18] [19], societal health [20], etc. By far, global warming has the highest climate impact on all living habitats [2] [21]. Global temperature data shows the average mean of Temperature Anomaly (TA) has remained positive since 1977 ( Figure 1 and Table 1). However, the impacts are not positive by any means. It rather suggests while global warming fluctuates in these four decades, the average TA has never gone below 0.00˚C [22] [23] [24], proving that global warming is not only faster than ever expected but is also progressive with no signs of conversions. It is alarming that since 2015, all TA figures are at the highest level ever and with 2016 and 2019 as the hottest and second hottest years on record (so far). Undoubtedly, this pattern, if continuing, will have a severe impact on ecology and human societies across the globe.
By assessing the publicly-available global temperature data, this study provides a comprehensive analysis of global warming patterns. This study focuses mostly on the period from 1977 onwards (due to the reason mentioned above), as it can be considered a turning point in our contemporary climatic conditions. This study portrays three key points: 1) difference in global warming patterns between north and south hemispheres, and reasons behind it; 2) correlation between global warming and increasing ocean surface temperature; and 3) global warming patterns and impacts on particular regions. With novel findings, this paper contributes to the studies on climate change and particularly global warming patterns. It is of great importance to comprehensively understand global warming patterns and its impacts at multiple scales, of which three scales of global, sub-regional, and regional are addressed here.

State of the Art and Research Methods
This study aims to shed light on three key areas in global warming patterns, especially those that are emerging in recent decades (since the late 1970s in particular). The patterns that are studied here are seen to be fluctuating in earlier decades, from the 1920s to the mid-1970s. However, as the TA has remained positive since 1977, we see minimal fluctuation and in fact, increasing global warming. Some of these have formed into recent global patterns that are important to study. The continuing patterns are worrying and they require scientific analysis and data-based analysis at multiple levels. In this study, we use the available data on recorded global temperature as well as grey literature that suggests global warming patterns in specific regions-hence, our approach here is data-based, which is valid for evaluation of the patterns and identifying the impacts at the global and regional levels.
The study is conducted in three parts. First, to identify the main differences between the north and south hemispheres. This is assessed based on the analysis of global warming differences in specific regions and using the available global maps that could address the differences. Second, we highlight specific patterns due to ocean surface temperature increase. This analysis benefits from the extensive literature on the topic as well as maps and temperature studies of ocean temperature data (see Table 1). And third, the study assesses recent impacts on particular regions, exploring maps on temperature variation as well as two simultaneous year-by-year and five-yearly analyses of shifting conditions in specific regions at the global level. In this part, we precisely highlight key examples that are more evident than those that are yet to be defined and/or scientifically assessed. All three are conducted based on the combined analysis of grey literature, data analysis on global temperature, and assessment of maps for specific emerging patterns. The following section provides the details of this evaluation study.

Assessing Global Warming at the Global Level
Recent climate models suggest accelerated warming and predict global warming that are expected to rise rapidly. The current climate modeling studies suggest 1.5˚C warming increase is likely to occur in 2030 [25], which is a decade earlier than the original IPCC's original projection of 2040 [26]. This suggests a major shift in increasing global warming that has accelerated in recent decades, and in particular in recent years. The existing climate modeling studies propose options for rapid response and adaptation strategies [25], and little thoughts are given to mitigating strategies that are harder to implement and achieve. This is realised as a major gap in responding to global warming impacts [2], as we continuously deal with minimised political determination and concerns that exist around decelerating the global economic growth. More importantly, existing research lacks knowledge on global warming patterns and the impacts it currently has and will have on the societies around the globe. But why is it important to assess global warming patterns? The answer is to reveal a better and bigger picture of our contemporary climatic situation, particularly at the larger scales, and before suggesting solutions that may not be so effective down the line.
Hence, the following three key points indicate that global warming patterns are already shaped or shaping since 1977, and their impacts will continue to be more drastic than what we estimate.

Global Warming Patterns in North and South Hemispheres
Comparatively, the Northern hemisphere is warmer down the south, mainly due to more land surfaces, more built areas, more population density, as well as higher production and consumption patterns. The relatively large body of An- tarctica, in comparison to the Arctic polar region, also plays a major part in keeping the southern water bodies cooler than the north ( Figure 2). Unexpectedly, the global scale data does not indicate a by-default higher temperature in higher density areas while it is proven that heat island effects are often more significant in those populated and dense built environments. For instance, Mongolia, a country with the lowest population density, currently suffers from rapid global warming effects. This is similar to other less populated regions of Canada, Siberia, Central Asia, and the Middle East. Therefore, global warming cannot be assessed at a country-level, but at a sub-regional or even continental scale. This proves the fact that climate issues do not take into consideration the physical boundaries of the built environments, cities, and populated regions. While city-level and regional-level initiatives to combat climate change impacts are essential, we require more of larger scale plans and strategies to speed up climate change mitigation [2] [27] [28] [29]. The larger scale can be from national-level (only for larger countries) and sub-regional levels to a larger scale of continental and even with global strategies.

Correlation between Global Warming and Increasing Ocean Surface Temperature
The relationship between ocean temperature and global warming are studied   [32]. This indicates we still have not seen the worst climatic conditions of this region, but the current trends indicate the situation will potentially worsen in the coming years.
On the 6th of February 2020, Antarctica's highest temperature was recorded at 18.3˚C, 0.8˚C higher than its previous highest record in 2015. Soon after, another this record was broken with an unexpectedly high temperature of 20.75˚C, worryingly much higher than the earlier record (both recorded and confirmed in February 2020). Also, other records suggest temperatures are constantly warming, which impacts the amount of ice lost annually from the Antarctic ice sheet by at least six-fold in the last four decades [33]. A similar pattern is also detected in the South Atlantic Ocean, particularly in the area between Atlantic Ocean and South and Pacific oceans, and consistently between the sub-region of southern Chile, Southern Argentina, and the Falkland Islands ( Figure 3).

Since 2012, there is a changing pattern that a sub-region of North Atlantic
Ocean started cooling down, affecting a more severe winter climate in Europe and North America. This is despite some signs of warming and temperature fluctuation in several regions [15] [34] [35] [36] [37]. The sub-regional cooling  impact is sudden and severe with colder temperatures in those regions. This abrupt cooling is also thought to be a potential reoccurrence of the region's rapid cooling previously experienced in the 1970s [38]. There are also some earlier signs of temperature decline from 2005 [39].

Global Warming Patterns and Impacts on Particular Regions
Existing scientific research studies, mostly assess specific global warming issues and various climatic impacts of enhanced equatorial warming [47], increasing global dryness [48] mainly due to CO 2 warming [49] [50] [51], cyclone intensity migration, shifting tropical cyclone translation speed, etc.
It is evidenced that there are regular El Niño and La Niña events [52] and particularly in the Equatorial Pacific region. In recent years, these events had more impacts on both Central/South America and Australasia [24].

Conclusions
While we already know the earth as a whole is warming, it is important to iden- This study discovers three key points associated with global warming patterns and their drastic impacts on particular areas. It questions existing research that only studies small scale or adaptation measures, and instead adds knowledge to existing research with more generic-but primary-findings. Finally, the study concludes that it is only at the global scale, that we can detect, assess, and understand global warming patterns. The impacts are at a relatively smaller scale of sub-regional, but show adverse results in different parts of the globe, particularly with a major difference between northern and southern hemispheres. The results here prove to be alarming, and with the continuing trends, the impacts will further increase, will emanate earlier, and will be more severe than previously predicted.

Availability of Data and Material
Primary data is available openly as a public source. The author would like to thank NASA-GISS for the available data on global temperature that are used primarily for the assessment of global warming patterns.

Code Availability
Not applicable.

Conflicts of Interest
The author declares no conflicts of interest regarding the publication of this paper.