الانبعاثات الكربونية منخفضة اليوم.

Because Arabic often uses a nominal sentence in the present tense, with no written or spoken verb for is / are.

So:

• الانبعاثات الكربونية = the carbon emissions
• منخفضة = low
• اليوم = today

Together, the sentence naturally means The carbon emissions are low today.

If you wanted past or future, Arabic would usually bring in a verb, for example:

• كانت الانبعاثات الكربونية منخفضة أمس = The carbon emissions were low yesterday

This is one of the most important rules in Arabic grammar:

Non-human plural nouns are usually treated grammatically as feminine singular when they agree with adjectives, verbs, and pronouns.

So even though الانبعاثات means emissions and is plural, the adjective is:

• منخفضة = feminine singular

not:

• منخفضات = feminine plural

This is normal and correct in Modern Standard Arabic.

A few similar examples:

• الكتب جديدة = The books are new
• السيارات سريعة = The cars are fast
• الأشجار طويلة = The trees are tall

All of these are non-human plurals, so the adjective appears in the feminine singular form.

الكربونية is an adjective modifying الانبعاثات.

So:

• الانبعاثات = emissions
• الكربونية = carbon / carbon-related

Together:

• الانبعاثات الكربونية = carbon emissions

In Arabic, adjectives normally come after the noun they describe, unlike English, where they often come before it.

So Arabic says literally:

• emissions carbon-related

but in natural English that becomes:

• carbon emissions

Because Arabic adjectives must agree with the noun they describe in definiteness as well as gender, number, and case.

Here, الانبعاثات has الـ, so it is definite:

• الانبعاثات = the emissions

Therefore the adjective must also be definite:

• الكربونية = the carbon-related

So:

• الانبعاثات الكربونية = the carbon emissions

If the noun were indefinite, the adjective would also be indefinite:

• انبعاثات كربونية = carbon emissions / some carbon emissions

In standard Arabic, a normal descriptive adjective usually comes after the noun.

So:

• الانبعاثات الكربونية = the carbon emissions

not normally:

• الكربونية الانبعاثات

That second order would not be the standard way to make a simple noun + adjective phrase.

This is a major difference from English:

• English: carbon emissions
• Arabic: emissions carbon-related

So when reading Arabic, it helps to expect the pattern:

• noun first
• adjective second

Because منخفضة is the predicate of the sentence, not an adjective inside the noun phrase.

Compare these two ideas:

1. Inside a noun phrase

   • الانبعاثات الكربونية = the carbon emissions
     Here, الكربونية describes the noun directly, so it matches definiteness.

2. As the predicate of the sentence

   • الانبعاثات الكربونية منخفضة = The carbon emissions are low
     Here, منخفضة is telling us something about the subject, so it is normally indefinite.

So Arabic often works like this:

• الجو جميل = The weather is beautiful
• الأسعار مرتفعة = The prices are high
• الانبعاثات الكربونية منخفضة = The carbon emissions are low

اليوم means today, and here it functions as an adverbial expression of time.

It tells us when the statement is true:

• الانبعاثات الكربونية منخفضة اليوم = The carbon emissions are low today

Arabic often places time words like this at the end, though other positions are also possible depending on style and emphasis.

For example:

• اليوم الانبعاثات الكربونية منخفضة = Today, the carbon emissions are low

Both are understandable, but the original order is very natural.

In fully vowelled, formal Arabic, the sentence would be:

الانبعاثاتُ الكربونيةُ منخفضةٌ اليومَ

Here is why:

• الانبعاثاتُ: nominative, because it is the subject of a nominal sentence
• الكربونيةُ: nominative, because it is an adjective matching الانبعاثات
• منخفضةٌ: nominative, because it is the predicate
• اليومَ: usually accusative as an adverbial expression of time

In normal everyday writing, these endings are usually omitted, so you typically see:

الانبعاثات الكربونية منخفضة اليوم

It is a nominal sentence.

A nominal sentence in Arabic begins with a noun or noun phrase, not a verb.

Here the structure is:

• الانبعاثات الكربونية = subject
• منخفضة = predicate
• اليوم = time expression

So the pattern is:

• subject + predicate + time expression

This is extremely common in Arabic for present-tense statements such as:

• الجو بارد = The weather is cold
• الطريق طويل = The road is long
• الانبعاثات الكربونية منخفضة اليوم = The carbon emissions are low today

In standard Arabic, no, not in this sentence.

Because الانبعاثات is a non-human plural, the normal agreement is feminine singular, so:

• correct: الانبعاثات الكربونية منخفضة
• not standard here: الانبعاثات الكربونية منخفضات

Using منخفضات would sound wrong in normal Modern Standard Arabic for this kind of noun.

So it is best to memorize this rule:

• human plural often takes true plural agreement
• non-human plural usually takes feminine singular agreement

Yes. Arabic word order can be flexible, especially with adverbials like اليوم.

For example:

• الانبعاثات الكربونية منخفضة اليوم
• اليوم الانبعاثات الكربونية منخفضة

Both can mean The carbon emissions are low today.

The difference is mainly one of emphasis:

• ending with اليوم feels neutral and natural
• starting with اليوم gives extra focus to today

But the original sentence is a very normal, standard way to say it.