When you need to add more information or detail to support an argument, provide further evidence, or introduce an additional point that enhances your discussion.
In addition
"Climate change affects not only atmospheric temperatures but also oceanic systems. In addition, the melting of polar ice caps accelerates sea-level rise, threatening coastal communities."
Furthermore
"Studies have shown that early childhood education improves cognitive development. Furthermore, it fosters social skills that are essential for long-term academic success."
Additionally
"The introduction of renewable energy sources has reduced carbon emissions in several countries. Additionally, these sources have created new jobs in the green energy sector."
Moreover
"The introduction of a new drug significantly decreased the incidence of heart attacks. Moreover, it was found to have fewer side effects than existing treatments."
Also
"Water scarcity is a growing concern in arid regions. Also, the overuse of water resources for agriculture has exacerbated this issue."
Too
"Regular physical activity improves cardiovascular health. It too has been shown to enhance mental well-being."
Besides
"Renewable energy is crucial for reducing carbon emissions. Besides, it reduces dependence on fossil fuels, which are finite and politically volatile."
Similarly
"Urbanization has led to significant changes in land use patterns. Similarly, it has caused shifts in local climate conditions due to the urban heat island effect."
Likewise
"The European Union has implemented stringent regulations on carbon emissions. Likewise, several other regions are adopting similar policies to combat climate change."
Specifically (when used to add more detail to a previous point)
"Renewable energy sources are becoming more efficient. Specifically, advances in solar panel technology have increased their energy conversion rates."
And
"Deforestation leads to a loss of biodiversity. And, it contributes to increased greenhouse gas emissions."